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Eye color prediction based on an individual's genetic information is of interest in the field of forensic genetics. In recent years, researchers have studied different genes and markers associated with this externally visible characteristic and have developed methods for its prediction. The IrisPlex represents a validated tool for homogeneous populations, though its applicability in populations of mixed ancestry is limited, mainly regarding the prediction of intermediate eye colors. With the aim of validating the applicability of this system in an admixed population from Argentina (n = 302), we analyzed the six single nucleotide variants used in that multiplex for eye color and four additional SNPs, and evaluated its prediction ability. We also performed a genotype-phenotype association analysis. This system proved to be useful when dealing with the extreme ends of the eye color spectrum (blue and brown) but presented difficulties in determining the intermediate phenotypes (green), which were found in a large proportion of our population. We concluded that these genetic tools should be used with caution in admixed populations and that more studies are required in order to improve the prediction of intermediate phenotypes.

Background Congenital sensorineural deafness (CSD) is the most common type of deafness in Dalmatian dogs. Objectives To use results of CSD screening in Dalmatian dogs in the United Kingdom in genetic analysis and to determine any changes in the prevalence of CSD in this breed over time. Animals A total of 8955 Dalmatian puppies undergoing hearing function screening using brainstem auditory evoked response (BAER) between July 1992 and February 2019. Methods Results of BAER testing and pigmentation phenotypic data were linked to the UK Kennel Club Dalmatian pedigree database. Mixed model analysis was used to estimate variance parameters. Results The overall prevalence of CSD was 17.8% (13.4%, unilateral; 4.4%, bilateral). Heritability of CSD was approximately 0.3 (across models) and significantly >0. Genetic correlations between CSD and blue irises (+0.6) and pigmented head patch (-0.86) were large in magnitude and significantly different form 0. Significant improving phenotypic and genetic trends were identified, likely as the result of selection against deafness, equivalent to avoiding breeding with the 4% to 5% of animals with the highest genetic risk of CSD. Conclusions and clinical importance A decrease in the prevalence and genetic risk of CSD implies breeders have been selecting for hearing dogs. Selective breeding based on estimated breeding values (EBVs) can help further decrease the prevalence of CSD in Dalmatians in the future.

Eye color is determined as a polymorphism and polygenic trait. Brown is the most common eye color in the world, accounting for about 79%, blue eye color for about 8-10%, hazel for 5%, and green for 2%. Rare-colored eyes include gray and red/violet. Different factors are involved in determining eye color. The two most important factors are the iris pigment and the way light is scattered from the iris. Gene expression determines the iris pigmentation and how much melanin is present in the eye, which is the number of melanin subunits that identify eye color. The genes involved in the pigmentation of single-nucleotide polymorphism (SNP) have a significant role; and even some genes are included only in the eye color through SNP. MicroRNAs also affect melanocyte synthesis, which is usually affected by the downregulation of essential genes involved in pigmentation. In this study, we assess the biochemical pathways of melanin synthesis, and the role of each gene in this pathway also has been examined in the signaling pathway that stimulates melanin synthesis.

Coat colour in livestock speciesis one of the most distinctive traits that characterise many different breeds. Pigmentation does not affect only skin and hairs but also the eyes. Few genomic studies in cattle and horses also investigated iris pigmentation, but no similar studies was conducted in pigs thus far. In this study we analysed eye colour diversity in a Large White pig population (n=897) and reported the results of genome-wide association studies based on several comparisonsincluding pigs having four main eye colour categories(three with both pigmented eyes of different brown grades: pale, 17.9%; medium, 14.8%; and dark, 54.3%; another one with both eyes completely depigmented, 3.8%) and heterochromia patterns (heterochromia iridis, i.e. depigmented iris sectors in pigmented irises, 3.2%; heterochromia iridium, i.e. a whole eye iris of depigmented phenotype and the other eye with the iris completely pigmented, 5.9%). Pigs were genotyped with the Illumina PorcineSNP60 BeadChip and GEMMA was used for the association analyses. The results indicated that the eye pigmented patterns (different grades of brown pigmentation), the total absence of pigmentation in the both eyes, and heterochromia iridis defect were under controlled of SLC45A2 (on chromosome 16, SSC16), EDNRB (SSC11) and KITLG (SSC5), respectively. In addition, to new candidate associations for the eye depigmented patterns were also identified for SNPs on two SSC4 regions (including two candidate genes: NOTCH2 and PREX2) and on SSC6, SSC8 and SSC14 (including COL17A1 as candidate gene). This study provided useful information to understand the genetic mechanisms affecting eye pigmentation in pigs.

Objective A genome-wide high-throughput single nucleotide polymorphism (SNP) typing method was tested with respect of the applicability to ancient and degraded DNA. The results were compared to mini-sequencing data achieved through single base extension (SBE) typing. The SNPs chosen for the study allow to determine the hair colors and eye colors of humans. Material and methods The DNA samples were extracted from the skeletal remains of 59 human individuals dating back to the Late Bronze Age. The 3,000 years old bones had been discovered in the Lichtenstein Cave in Lower Saxony, Germany. The simultaneous typing of 24 SNPs for each of the ancient DNA samples was carried out using the 192.24 Dynamic Array (TM) by Fluidigm (R). Results Thirty-eight of the ancient samples (=64%) revealed full and reproducible SNP genotypes allowing hair and eye color phenotyping. In 10 samples (=17%) at least half of the SNPs were unambiguously determined, in 11 samples (=19%) the SNP typing failed. For 23 of the 59 individuals, a comparison of the SNP typing results with genotypes from an earlier performed SBE typing approach was possible. The comparison confirmed the full concordance of the results for 90% of the SNP typings. In the remaining 10% allelic dropouts were identified. Discussion The high genotyping success rate could be achieved by introducing modifications to the preamplification protocol mainly by increasing the DNA input and the amplification cycle number. The occurrence of allelic dropouts indicates that a further increase of DNA input to the preamplification step is desirable.

This study examined 266 individuals from various populations including African American, East Asian, South Asian, European, and mixed populations to evaluate the ForenSeq™ Signature Prep Kit Primer Mix B. Focus was placed on phenotypic and biogeographical ancestry predictions by Illumina's Universal Analysis Software (UAS). These outcomes were compared to those obtained through web-tools developed at the Erasmus Medical Center (EMC) and available from the Forensic Resource/Reference on Genetics-knowledge base (FROG-kb), as well as to eye color predictions by the 8-plex system. Due to drop-outs, predictions for eye and hair color by UAS failed for various samples in each run. By including reads below thresholds, predictions could be obtained for all samples through the web-tools. Eye and hair color predictions for African Americans, East Asians, and South Asians showed no errors. Difficulties however, were noted in intermediate (neither blue nor brown) eye color predictions. These were mitigated by the 8-plex system through exclusion of one eye color (e.g. "not brown"). Additionally, notable discrepancies were observed in hair color predictions, where some black/dark-brown haired individuals were predicted to have blond hair. Overall, ancestry predictions were more accurate by FROG-kb compared to UAS, which did not predict South Asian ancestry, particularly Indian individuals.

PURPOSE Understanding the association of iris colour and myopia may provide further insights into the role of the wavelength of lights in the pathophysiology of myopia. We aim to assess the association of iris colour and myopia in a school-based sample of Chinese students. METHODS Two thousand three hundred and forty-six Year 7 students from 10 middle schools (93.5% response rate) aged 13-14 years in Mojiang, a small county located in Southwestern China, participated in the study. We obtained standardised slit lamp photographs and developed a grading system assessing iris colour (higher grade denoting a darker iris). Refractive error was measured after cycloplegia using an autorefractor by optometrists or trained technicians. An IOLMaster (www.zeiss.com) was used to measure ocular biometric parameters including axial length (AL). RESULTS Of all the study participants, 693 (29.5%) were affected by myopia with the prevalence estimates being higher in girls (36.8%; 95% confidence interval [CI]: 34.0, 39.6) than in boys (22.8%; 95% CI: 20.4, 25.1) (p

Background Despite suffering high ultraviolet radiation levels, few data on malignant melanoma (MM) in Macaronesia are available. Methods Observational study of cutaneous MM cases diagnosed during a period of 12 years at a tertiary hospital in Canary Islands. Results A total of 532 patients (female/male = 1.4) with an average age of 56 years were included; 5% developed more than one MM, and 7% reported family history of MM. Phototype II (43%), dark eyes (41%), and dark hair (41%) predominated. There was a lower frequency of light-colored hair and eyes in those born in the Canary Islands. The most frequent locations of MM were on the back for men (37%) and on the lower extremities for women (35%). Among the infiltrating tumors (83%), the (median) thickness was 1.07 mm (women, 0.90 mm; men, 1.21 mm). Anatomopathological ulceration (AU) and a mitotic rate ≥1 mitosis/mm2 (HMR) were recorded in 27% of patients. Patients with regional disease constituted 12% of the population. The most common stage was IA (34%). Melanoma-specific survival (MSSV) decreased significantly with thickness, presence of AU, HMR, and sentinel lymph node disease. These four variables were independent prognostic factors. The five-year MSSV varied between 100% (stage IA) and 39% (stage IIIC). Conclusions The characteristics of the patients were similar to those published in datasets from continental Europe, although the pigmentary features were darker in those originating from Macaronesia. The prognostic parameters described in the 7th edition of the American Joint Committee on Cancer (AJCC) independently predict MSSV in our patients.

The use of the physical appearance of the deceased has become more important because the available antemortem information for comparisons may consist only of a physical description and photographs. Twenty-one articles dealing with the identification based on the physiognomic features of the human body were selected for review and were divided into four sections: (i) visual recognition, (ii) specific facial/body areas, (iii) biometrics, and (iv) dental superimposition. While opinions about the reliability of the visual recognition differ, the search showed that it has been used in mass disasters, even without testing its objectivity and reliability. Specific facial areas being explored for the identification of dead; however, their practical use is questioned, similarly to soft biometrics. The emerging dental superimposition seems to be the only standardized and successfully applied method for identification so far. More research is needed into a potential use of the individualizing features, considering that postmortem changes and technical difficulties may affect the identification.

The purpose of this study was to investigate the inheritance of red eyes in ornamental koi, a variant of Common Carp Cyprinus carpio. The study included crossing fish with different eye color phenotypes and analyzing fish segregations in progenies. In progeny 1, obtained by crossing a red-eyed, yellow male with a black-eyed, white-red female, the segregation “red eyes : black eyes” in juveniles did not differ significantly from the 1:1 Mendelian ratio. In two progenies obtained by crosses of red-eyed fish from progeny 1, the segregations of larvae with light and dark lenses and the segregations “red eyes : black eyes” in juveniles not having black pigmentation on the body did not differ from the 3:1 Mendelian ratio. In two progenies obtained by crosses of black-eyed fish from progeny 1, larvae with only dark lenses and juveniles with only black eyes were observed. Based on these data, it was suggested that the appearance of red eyes in koi is controlled by a dominant mutation of one gene (R/r); ko...

Purpose This study aims to assess the birth prevalence of iris colour among newborns in a prospective, healthy, full-term newborn cohort. Methods The Newborn Eye Screening Test (NEST) study is a prospective cohort study conducted at Lucile Packard Children's Hospital at Stanford University School of Medicine. A paediatric vitreoretinal specialist (DMM) reviewed images sent to the Byers Eye Institute telemedicine reading centre and recorded eye colour for every infant screened. Variables were graphed to assess for normality, and frequencies per subject were reported for eye colour, sex, ethnicity and race. Results Among 192 subjects screened in the first year of the NEST study with external images of appropriate quality for visualization of the irides, the birth prevalence of iris colour was 63.0% brown, 20.8% blue, 5.7% green/hazel, 9.9% indeterminate and 0.5% partial heterochromia. The study population was derived from a quaternary care children's hospital. We report the birth prevalence of iris colour among full-term newborns in a diverse prospective cohort. Conclusion The study demonstrates a broad range of iris colour prevalence at birth with a predominance of brown iris coloration. Future studies with the NEST cohort will assess the change in iris colour over time and whether the frequencies of eye colour change as the child ages.

Black-eyed Locusta migratoria appeared in albino locusts as a result of crossing between a short-winged strain originating from Tsushima Island, Japan, and an albino strain originating from Okinawa Island. The black eye trait was recessive to the white eye trait because the crosses between black- and white-eyed albino locusts produced only individuals with white eyes in the F1 generation. In the F2 generation, black- and white-eyed individuals appeared in a ratio of 1:3, indicating that the black eye trait was controlled by a simple Mendelian unit. The black eye trait showed no genetic association with other traits including wing morph, adult body dimensions and classical morphometric ratios such as hind femur length / head width and forewing length / hind femur length.

In this study, we present a new quantitative method to measure iris colour based on high‐resolution photographs. We applied this method to analyse iris colour variation in a sample of individuals of East Asian, European and South Asian ancestry. We show that measuring iris colour using the coordinates of the CIELAB colour space uncovers a significant amount of variation that is not captured using conventional categorical classifications, such as ‘brown’, ‘blue’ or ‘green’. We tested the association of a selected panel of polymorphisms with iris colour in each population group. Six markers showed significant associations with iris colour in the European sample, three in the South Asian sample and two in the East Asian sample. We also observed that the marker HERC 2 rs12913832, which is the main determinant of ‘blue’ versus ‘brown’ iris colour in European populations, is also significantly associated with central heterochromia in the European sample.

Objectives The main goals of this study are to 1) quantitatively measure skin, hair, and iris pigmentation in a diverse sample of individuals, 2) describe variation within and between these samples, and 3) demonstrate how quantitative measures can facilitate genotype-phenotype association tests. Materials and Methods We quantitatively characterize skin, hair, and iris pigmentation using the Melanin (M) Index (skin) and CIELab values (hair) in 1,450 individuals who self-identify as African American, East Asian, European, Hispanic, or South Asian. We also quantify iris pigmentation in a subset of these individuals using CIELab values from high-resolution iris photographs. We compare mean skin M index and hair and iris CIELab values among populations using ANOVA and MANOVA respectively and test for genotype-phenotype associations in the European sample. Results All five populations are significantly different for skin (P

Lemurs, the living primates most distantly related to humans, demonstrate incredible diversity in behaviour, life history patterns and adaptive traits. Although many lemur species are endangered within their native Madagascar, there is no high-quality genome assembly from this taxon, limiting population and conservation genetic studies. One critically endangered lemur is the blue-eyed black lemur Eulemur flavifrons. This species is fixed for blue irises, a convergent trait that evolved at least four times in primates and was subject to positive selection in humans, where 5' regulatory variation of OCA2 explains most of the brown/blue eye colour differences. We built a de novo genome assembly for E. flavifrons, providing the most complete lemur genome to date, and a high confidence consensus sequence for close sister species E. macaco, the (brown-eyed) black lemur. From diversity and divergence patterns across the genomes, we estimated a recent split time of the two species (160 Kya) and temporal fluctuations in effective population sizes that accord with known environmental changes. By looking for regions of unusually low diversity, we identified potential signals of directional selection in E. flavifrons at MITF, a melanocyte development gene that regulates OCA2 and has previously been associated with variation in human iris colour, as well as at several other genes involved in melanin biosynthesis in mammals. Our study thus illustrates how whole-genome sequencing of a few individuals can illuminate the demographic and selection history of nonmodel species.

Background Incidences of primary cutaneous melanoma (CM) have risen over the last few decades, mainly among populations of White European extraction. Some risk factors for melanoma have been clearly established, but other potential risk factors, such as exposure to pesticides, are currently under study. Methods A case–control study on melanoma was conducted during 2012 and 2013 at three dermatological reference centers in Porto Alegre, Brazil. A total of 191 CM patients and sex- and age-matched control subjects were enrolled in the study. Data on domestic and occupational use of pesticides and the risk factors already established for CM were collected. Multivariate logistic regression was used to study the association between exposure to pesticides and melanoma risk. Results Subjects exposed to pesticides had twice the level of risk for melanoma (odds ratio [OR] 2.03, 95% confidence interval [CI] 1.03–6.89). When pesticides were used indoors for >10 years, the risk for CM increased further (OR 2.84, 95% CI 1.56–5.33). A high frequency of indoor use of pesticides (four or more times per year) was associated with a 44% increase in the risk for melanoma (OR 1.44, 95% CI 1.11–3.49). The domestic use of pesticides outdoors was not associated with increased risk. Subjects exposed to pesticides at an occupational level were at four times greater risk than subjects who were not occupationally exposed (OR 4.23, 95% CI 1.94–6.31). Conclusions These findings indicate that the general use of pesticides, particularly indoor domestic use, frequently and over a long period, may be an independent environmental risk factor for CM.

Sunlight exposure induces signalling pathways leading to the activation of melanin synthesis and tanning response. MicroRNAs (miRNAs) can regulate the expression of genes involved in pigmentation pathways by binding to the complementary sequence in their 3'untranslated regions (3'UTRs). Therefore, 3'UTR SNPs are predicted to modify the ability of miRNAs to target genes, resulting in differential gene expression. In this study, we investigated the role in pigmentation and sun-sensitivity traits, as well as in melanoma susceptibility, of 38 different 3'UTR SNPs from 38 pigmentation-related genes. A total of 869 individuals of Spanish origin (526 melanoma cases and 343 controls) were analysed. The association of genotypic data with pigmentation traits was analysed via logistic regression. Web-based tools for predicting the effect of genetic variants in microRNA-binding sites in 3'UTR gene regions were also used. Seven 3'UTR SNPs showed a potential implication in melanoma risk phenotypes. This association is especially noticeable for two of them, rs2325813 in the MLPH gene and rs752107 in the WNT3A gene. These two SNPs were predicted to disrupt a miRNA-binding site and to impact on miRNA-mRNA interaction. To our knowledge, this is the first time that these two 3'UTR SNPs have been associated with sun-sensitivity traits. We state the potential implication of these SNPs in human pigmentation and sensitivity to sunlight, possibly as a result of changes in the level of gene expression through the disruption of putative miRNA-binding sites.

The gene vermilion encodes tryptophan 2,3-dioxygenase, part of the ommochrome pathway, and is responsible for the dark pigmented eyes in some insects, including beetles. Using RNA interference, we targeted the vermilion gene ortholog in embryos and pupae of the yellow mealworm, Tenebrio molitor, resulting in larvae and adults, respectively, that lacked eye pigment. RNA-Seq was used to analyze the impact of vermilion-specific RNA interference on gene expression. There was a 425-fold reduction in vermilion gene expression (p = 0.0003), as well as significant (p < 0.05) differential expression of 109 other putative genes, most of which were downregulated. Enrichment analysis of Gene Ontology terms found in the differentially expressed data set included genes known to be involved in the ommochrome pathway. However, enrichment analysis also revealed the influence of vermilion expression on genes involved in protein translocation to the endoplasmic reticulum, signal transduction, G-protein-coupled receptor signaling, cell-cycle arrest, mannose biosynthesis, and vitamin transport. These data demonstrate that knockdown of vermilion in T. molitor results in complete loss of eye color (white-eyed phenotype) and identify other interrelated genes in the vermilion metabolic pathway. Therefore, a dominant marker system based on eye color can be developed for the genetic manipulation of T. molitor to increase the value of mealworms as an alternative food source by decreasing negative traits, such as disease susceptibility, and increasing desired traits, such as protein content and vitamin production.

How many distinct molecular paths lead to the same phenotype? One approach to this question has been to examine the genetic basis of convergent traits, which likely evolved repeatedly under a shared selective pressure. We investigated the convergent phenotype of blue iris pigmentation, which has arisen independently in four primate lineages: humans, blue-eyed black lemurs, Japanese macaques, and spider monkeys. Characterizing the phenotype across these species, we found that the variation within the blue-eyed subsets of each species occupies strongly overlapping regions of CIE L*a*b* color space. Yet whereas Japanese macaques and humans display continuous variation, the phenotypes of blue-eyed black lemurs and their sister species (whose irises are brown) occupy more clustered subspaces. Variation in an enhancer of OCA2 is primarily responsible for the phenotypic difference between humans with blue and brown irises. In the orthologous region, we found no variant that distinguishes the two lemur species or associates with quantitative phenotypic variation in Japanese macaques. Given the high similarity between the blue iris phenotypes in these species and that in humans, this finding implies that evolution has used different molecular paths to reach the same end. Am J Phys Anthropol 151:398–407, 2013.© 2013 Wiley Periodicals, Inc.

Our aim was to examine the association between ethnicity, phenotype, sun behavior and other characteristics, and constitutive and relative facultative skin pigmentation. A total of 191 participants were recruited, with a mean age of 7.6 years (SD 3.4), during 2009-2011 from Maternal and Child Health Centres (MCHC) and schools in Melbourne, Australia. Parental questionnaire data were obtained on sun behavior and examination consisted of noting the child's natural skin, hair and eye color, ethnicity, nevi count and spectrophotometric melanin density (MD). Constitutive skin pigmentation was estimated from buttock MD. Relative facultative skin pigmentation was estimated by hand compared with buttock absorption. Ethnicity, hair color and skin color were associated with constitutive and facultative skin pigmentation on univariate analysis. Higher ambient ultraviolet radiation (UVR) in the past month, greater freckling, greater nevi and increased sun exposure over the past year were related to darker facultative skin pigmentation. Sun exposure over the life course was not. The two skin charts accounted for 39.7% and 21.4% of buttock MD, respectively. Relative facultative skin pigmentation is associated with recent UVR levels, not life-course sun exposure. Relative facultative skin pigmentation may not be a useful measure of sun exposure over the early life course. Skin color charts can be used to assess constitutive skin pigmentation if spectrophotometry is not available.

A female, eight-year-old, mixed-breed blue-eyed dog was presented for ophthalmic evaluation because its left eye had "changed color" one year previously. The before left eye was enucleated and submitted for evaluation. Histopathological analysis revealed an invasive neoplastic mass effacing most of the ventral aspect of the iris stroma. A diagnosis of an anterior uveal spindle cell tumor was made. Immunohistochemical results were strongly suggestive of a schwannoma, but some smooth muscle differentiation was also observed. Two and a half years after therapeutic enucleation there was no evidence of neoplasm recurrence or metastasis.

Prediction of visible traits from genetic data in certain forensic cases may provide important information that can speed up the process of investigation. Research that has been conducted on the genetics of pigmentation has revealed polymorphisms that explain a significant proportion of the variation observed in human iris color. Here, on the basis of genetic data for the six most relevant eye color predictors, two alternative Bayesian network model variants were developed and evaluated for their accuracy in prediction of eye color. The first model assumed eye color to be categorized into blue, brown, green, and hazel, while the second variant assumed a simplified classification with two states: light and dark. It was found that particularly high accuracy was obtained for the second model, and this proved that reliable differentiation between light and dark irises is possible based on analysis of six single nucleotide polymorphisms and a Bayesian procedure of evidence interpretation.

Our understanding of the genetic archi- tecture of iris color is still limited. This is partly related to difficulties associated with obtaining quantitative measurements of eye color. Here we introduce a new automated method for measuring iris color using high resolution photographs. This method extracts color measurements in the CIE 1976 L*a*b* (CIELAB) color space from a 256 by 256 pixel square sampled from the 9:00 meridian of the iris. Color is defined across three dimensions: L* (the lightness coordinate), a* (the red- green coordinate), and b* (the blue-yellow coordinate). We applied this method to a sample of individuals of diverse ancestry (East Asian, European and South Asian) that was genotyped for the HERC2 rs12913832 polymorphism, which is strongly associated with blue eye color. We identified substantial variation in the CIELAB color space, not only in the European sample, but also in the East Asian and South Asian samples. As expected, rs12913832 was significantly associated with quantitative iris color measurements in subjects of European ancestry. However, this SNP was also strongly associated with iris color in the South Asian sample, although there were no participants with blue irides in this sample. The usefulness of this method is not restricted only to the study of iris pigmentation. High-resolution pictures of the iris will also make it possible to study the genetic variation involved in iris textural patterns, which show substantial heritability in human populations. Am J Phys Anthropol 147:141- 149, 2012. V C 2011 Wiley Periodicals, Inc.

Objective To present results from the United States (US) Cluster Headache Survey including data on cluster headache demographics, clinical characteristics, suicidality, diagnostic delay, triggers, and personal burden. Background There are few large-scale studies looking at cluster headache patients and none from the USA. This manuscript will present data from The US Cluster Headache Survey, the largest survey ever completed of cluster headache patients living in the USA. Methods The total survey was composed of 187 multiple-choice questions that dealt with issues related to cluster headache including demographics, clinical characteristics, comorbid medical conditions, family history, triggers, smoking history, and personal burden. The survey was placed on a Web site from October through December 2008. Results A total of 1134 individuals completed the survey (816 male, 318 female). Some key highlights from the survey include the following: (1) diagnostic delay: there remains a significant diagnostic delay for cluster headache patients on average 5+ years with only 21% receiving a correct diagnosis at time of initial presentation. (2) Suicidality: suicidal ideations are substantial, occurring in 55%. (3) Eye color: the predominant eye color in cluster headache patients is brown and blue, not hazel as suggested in previous descriptions. (4) Laterality: cluster headache has a right-sided predominance. (5) Attack profile: in US cluster headache sufferers, most attacks occur between early evening and early morning hours with peak time of headache onset between midnight and 3 am; the circadian periodicity for cluster headache is present but is not as predominant in the population as previously thought. (6) Triggers: beer is the most common type of alcohol trigger in US cluster headache patients; noted migraine triggers such as weather changes and smells are also very common cluster headache triggers. (7) Medical comorbidities: peptic ulcer disease does not have a high prevalence in US cluster headache patients as suggested by previous literature; cluster headache is associated with a low prevalence of cardiac disease as well as cerebrovascular disease even though the majority of patients are chronic heavy smokers. In US cluster headache sufferers, there appears to be comorbidity with restless leg syndrome, and this has not been demonstrated in non-US cluster headache populations. (8) Personal burden: cluster headache is disabling to the individual as almost 20% of cluster headache patients have lost a job secondary to cluster headache, while another 8% are out of work or on disability secondary to their headaches. Conclusion Some findings from the US Cluster Headache Survey expound on what is currently known about cluster headache, while some of the results contradict what has been previously written, while other information is completely new about this fascinating headache disorder.

This paper examines the development and consistency of children's (4, 7, 10, and 14 years) naïve concepts of inheritance using three tasks. A modified adoption task asked participants to distinguish between biological and social parentage in their predictions and explanations of the origins of different feature types (physical characteristics, disabilities, and personality traits). The causal mechanisms task asked participants to rate their preference for various mechanisms of inheritance for physical features. The family relatedness task required participants to provide judgements on the relatedness of family members and explain their understanding of kinship terms. Developmental trends were revealed in all three tasks. There was a trend towards increased consistency in judgements across tasks with age, but low correlations between explanations given in different task contexts. Findings are discussed with reference to the onset and variability of inheritance concepts and the implications for education and future research.

Objectives The aim of this study was to test the efficacy of latanoprost in eyelash alopecia areata (AA). Design This study is a 2-year prospective, non-blinded, non-randomized, bilateral eyelash alopecia controlled study. Setting The setting of this study was Trichology Unit, Virgen Macarena University Hospital, Seville, Spain. Patients We conducted a survey of 54 subjects with AA universalis treated with the protocol of the Trichology Unit of our Department. Control group comprised 10 subjects who received injections of 0.5 mg/cm2 of triamcinolone acetonide (TAC) in their eyebrows and 1 mg/cm2 of TAC injections in affected scalp. The treatment group included 44 subjects who received the same treatment as the control group in scalp and eyebrows but they also applied a drop of latanoprost 0.005% (50 μg/mL) ophthalmic solution in their eyelid margins every night. Subjects were reviewed every 3 months for 2 years. Results Forty subjects finished the study and four subjects were lost to follow-up. In the treatment arm of this study, the course was well tolerated and uncomplicated. Both investigators and patients evaluated the regrowth. The results we obtained were: complete regrowth in 17.5%, moderate regrowth in 27.5%, slight regrowth in 30% and without response in 25%. Moderate and total regrowth constituted a cosmetically acceptable response. The therapy was continuous and the response remained without any side effects. No patients had cosmetically acceptable eyelash regrowth in the control group. Conclusions Latanoprost may be an effective drug in the treatment of eyelash AA because it induces acceptable responses (total and moderate) in 45% of the patients. A formal, blinded prospective unilateral controlled study will permit further understanding about this promising therapeutic agent for eyelash AA.

Purpose: To investigate the effect of iris pigment and pupil size in ultraviolet radiation (UVR)-induced cataract. Methods: Brown-Norway rats (pigmented) and Fischer-344 rats (non-pigmented) were unilaterally exposed in vivo to 5 kJ/m2 UVR. Each strain was split into two groups, each receiving either mydriatic (tropicamide) or miotic (pilocarpine) eye-drops. One week after exposure, the degree of ocular inflammation and damage in the anterior segment was determined. The lenses were extracted, photographed and the degree of forward light scattering (cataract) was quantified. Results: The cataract types differed between the two strains. All Fischer rats developed macroscopically identifiable UVR cataract while only 41% of Brown-Norway rats did so. All groups except the miotic Brown-Norway developed significant light scattering. The Fischer rats developed 3–4-fold more lens light scattering than the Brown-Norway rats. The miotic Fischer group exhibited significantly more light scattering than the mydriatic Fischer group. There was no significant difference in light scattering between the two Brown-Norway groups. There was a correlation between ocular inflammation and degree of light scattering, with Brown-Norway rats exhibiting less inflammation and lens light scattering. Conclusions: Pigmented rats develop less UVR cataract and less ocular inflammation than non-pigmented rats. Pupil size plays a smaller role in UVR cataract development in pigmented rats than in non-pigmented. The role of UVR-induced ocular inflammation in cataract development is still ambiguous.

The cause of Paget's disease of bone (PDB) is unknown. In an attempt to ascertain the proportion of familial cases and evaluate the influence of genetic factors on the occurrence of the disease, a study was undertaken based on 35 PDB patients from our Unit. Their families were investigated, with the participation of a total of 128 first-degree relatives. Fourteen (40%) of these 35 index cases had at least one other first-degree relative affected with PDB and were defined as “familial.” The remaining 21 (60%) were considered “sporadic.” The frequency of males in the familial cases (79%) was significantly higher than among the sporadics (29%; p ≤ 0.01). Mean age at diagnosis (63.1 12.6 vs. 713 ± 8.7; p ≤ 0.02), proportion of polyostotic cases (85.7% vs. 52.4%, p ≤ 0.05), and mean number of involved bones per patient (436 ± 2.50 vs. 233 ± 1.93, p ≤ 0.01) differ significantly in the familial and sporadic groups. The disease appears to be transmitted via both paternal and maternal sides, and pedigree analysis suggested an autosomal dominant inheritance or multifactorial mechanism. Apart from green-and-blue eye color, which was clearly associated with familial grouping (OR 6.25, 95% CI 1.15–37.16, p ≤ 0.01), crude analysis on several genetically based traits and environmental variables revealed no other significant differences between the groups. The adjusted odds ratio estimated for green-and-blue eye color was 2.92 (95% CI 038–22.74). Although additional studies will be required to determine whether the high proportion of familial cases and the differences between these and the sporadic cases also exist in different geographic areas, our data support the existence of two distinct subtypes of PDB.

Almost all mammals have brown or darkly-pigmented eyes (irises), but among primates, there are some prominent blue-eyed exceptions. The blue eyes of some humans and lemurs are a striking example of convergent evolution of a rare phenotype on distant branches of the primate tree. Recent work on humans indicates that blue eye color is associated with, and likely caused by, a single nucleotide polymorphism (rs12913832) in an intron of the gene HERC2, which likely regulates expression of the neighboring pigmentation gene OCA2. This raises the immediate question of whether blue eyes in lemurs might have a similar genetic basis. We addressed this by sequencing the homologous genetic region in the blue-eyed black lemur (Eulemur macaco flavifrons; N = 4) and the closely-related black lemur (Eulemur macaco macaco; N = 4), which has brown eyes. We then compared a 166-bp segment corresponding to and flanking the human eye-color-associated region in these lemurs, as well as other primates (human, chimpanzee, orangutan, macaque, ring-tailed lemur, mouse lemur). Aligned sequences indicated that this region is strongly conserved in both Eulemur macaco subspecies as well as the other primates (except blue-eyed humans). Therefore, it is unlikely that this regulatory segment plays a major role in eye color differences among lemurs as it does in humans. Although convergent phenotypes can sometimes come about via the same or similar genetic changes occurring independently, this does not seem to be the case here, as we have shown that the genetic basis of blue eyes in lemurs differs from that of humans.

Using non-invasive methods we report here that the stability of the pre-corneal tear film is lower in the brown eye than in the blue eye. The average stability in the blue eye is 15.8 sec (SD +/- 5.8) and in the brown eye it is 12.3 sec (SD +/- 2.9). On average, instillation of topical anaesthetics, benoxinate hydrochloride (0.4%) or amethacaine hydrochloride (0.5%), depress the stability of the pre-corneal tear film in blue eyes but not in brown eyes.

The corneal sensation of diabetic patients undergoing pan retinal photocoagulation for the treatment of proliferative retinopathy was measured using the Cochet-Bonnet aesthesiometer. Insulin dependent and non-insulin dependent diabetics both showed significantly decreased corneal sensitivity, and there was no significant change following pan-retinal photocoagulation. Insulin dependent diabetics with proliferative retinopathy had been diagnosed for a significantly longer period than non-insulin dependent diabetics, but had better corneal sensitivity than the latter group. Male patients were more likely to have brown irides, whereas there was a preponderance of blue irides amongst the females. Patients with blue irides also had significantly lower sensitivity than patients with brown irides. The results are discussed.

Background: Deafness in dogs is frequently associated with the pigment genes piebald and merle. Little is known about the prevalence of deafness in dogs carrying the merle allele. Objective: To determine the prevalence of deafness in dogs heterozygous and homozygous for the merle allele of the mouse Silver pigment locus homolog (SILV) gene. Animals: One hundred and fifty-three privately owned merle dogs of different breeds and both sexes. Methods: Hearing was tested by brainstem auditory-evoked response and classified as bilaterally hearing, unilaterally deaf, or bilaterally deaf. DNA from buccal cells was genotyped as either heterozygous or homozygous for the merle allele. Deafness association tests among merle genotype, eye color, and sex were performed by the χ2 test. Results: Deafness prevalence in merles overall was 4.6% unilaterally deaf and 4.6% bilaterally deaf. There was a significant association between hearing status and heterozygous versus homozygous merle genotype. For single merles (Mm), 2.7% were unilaterally deaf and 0.9% were bilaterally deaf. For double merles (MM), 10% were unilaterally deaf and 15% were bilaterally deaf. There was no significant association with eye color or sex. Conclusions: Deafness prevalence in merle dogs was greater than that in some dog breeds homozygous for the piebald gene, such as the English Cocker Spaniel, but comparable to, or lower than, that in the Dalmatian and white Bull Terrier. Dogs homozygous for the merle allele were significantly more likely to be deaf than heterozygotes.

Microphthalmia-associated transcription factor (MITF) is involved in white spotting and deafness associated with lack of pigmentation in human and mice. In the present study, we employed MITF-associated markers to evaluate MITF as a candidate for canine congenital sensorineural deafness (CCSD) in Dalmatian dogs. We performed an association study using MITF flanking and intragenic markers for 88 Dalmatian dogs of different hearing and eye pigmentation status. A significant association was identified for MITF-related markers with CCSD and blue iris colour. We conclude that MITF might play a role in CCSD and blue eye colour in Dalmatian dogs.

In this study, we assessed the role of melanocortin-1 receptor (MC1R) and agouti signalling protein (ASIP) polymorphisms in cutaneous melanoma and basal cell carcinoma (BCC) development in a Polish population. We enrolled 108 patients with skin malignant melanoma (MM) and 102 patients with BCC. The control group consisted of 93 non-red haired patients, without history of skin cancers and 30 healthy individuals with red hair colour (RHC) phenotype. The complete MC1R exon was sequenced and the A8818G polymorphism of the ASIP gene was analysed using the SnaPshot protocol. Selected MC1R mutations were additionally examined using a convenient minisequencing assay. The study confirmed the important role of MC1R R variants in determining physiological variation in hair and skin colour. Our data show that individuals with R mutations had a 3.7-fold increase in melanoma risk and a 3.3-fold increase in BCC risk. Especially, variant R151C significantly increased the risk of both MM and BCC. The studied ASIP polymorphism was found not to be associated with MM or BCC. Stratified analysis showed that the association between MC1R mutations and the risk of MM and BCC was not significantly influenced by subjects' pigmentation characteristics or the 8818G ASIP variant. Further research is necessary, especially involving analysis of interactions between variation in MC1R and other genes, to find out if analysis of MC1R polymorphisms could be of any importance for skin cancer prevention.

Recent research has identified polymorphic trichromacy in three diurnal strepsirrhines: Coquerel's sifaka (Propithecus coquereli), black and white ruffed lemurs (Varecia variegata), and red ruffed lemurs (V. rubra). Current hypotheses suggest that the transitions to diurnality experienced by Propithecus and Varecia were necessary precursors to their independent acquisitions of trichromacy. Accordingly, cathemeral lemurs are thought to lack the M/L opsin gene polymorphism necessary for trichromacy. In this study, the M/L opsin gene was sequenced in ten cathemeral blue-eyed black lemurs (Eulemur macaco flavifrons). This analysis identified a polymorphism identical to that of other trichromatic strepsirrhines at the critical amino acid position 285 in exon 5 of the M/L opsin gene. Thus, polymorphic trichromacy is likely present in at least one cathemeral Eulemur species, suggesting that strict diurnality is not necessary for trichromacy. The presence of trichromacy in E. m. flavifrons suggests that a re-evaluation of current hypotheses regarding the evolution of strepsirrhine trichromacy may be necessary. Although the M/L opsin polymorphism may have been independently acquired three times in the lemurid–indriid clade, the distribution of opsin alleles in lemurids and indriids may also be consistent with a common origin of trichromacy in the last common ancestor of either the lemurids or the lemurid–indriid clade. Am. J. Primatol. 71:86–90, 2009. © 2008 Wiley-Liss, Inc.

Background Malignant melanoma is an increasing public health problem worldwide; accordingly, identification of the constitutional and environmental factors which contribute to the development of the disease, and hence identification of the individuals at high risk of melanoma, is an indispensable step in all primary prevention efforts. Objectives This paper aims to assess the prevalence of different pigmented lesions among schoolchildren and to investigate their relationship with phenotypic pigmentary characteristics, sun exposure and other factors. Patients/methods A cross-sectional study was performed in two secondary schools in Szeged, Hungary. A total of 1320 schoolchildren, aged 14 to 18 years, underwent a whole-body skin examination. A standardized questionnaire was used to collect data on phenotypic, sun exposure and other variables. Results One to 10 common melanocytic naevi were found in 27% of the participants, and the naevus numbers were in the range of 10–100 in 67%; 5.4% of them had more than 100 common melanocytic naevi. The prevalence of clinically atypical naevi was 24.3%. Statistically significant associations were found between the number of pigmented lesions and gender, hair colour, eye colour, skin phototype, a history of severe painful sunburns and a family history of a large number of melanocytic naevi. Conclusion Our study population displayed a markedly high prevalence of clinically atypical melanocytic naevi. Moreover, a considerable proportion of the investigated individuals had multiple common melanocytic naevi. Since the presence of a large number of melanocytic naevi is a strong predictor for future melanoma development, health educational programmes on melanoma prevention should be aimed at young age groups.

Background Sun exposure, light skin pigmentation, and melanocortin 1 receptor (MC1R) gene variants are independent risk factors for skin cancer. The Canary Islands have a sunny and temperate climate, but data regarding the phenotypic and genotypic risk factors among the population are lacking. Methods The main phenotypic features (skin color, hair color, eye color, and freckling) of 5116 healthy individuals are described. The genotypic findings of six MC1R gene variants (V60L, D84E, R150C, R160W, R163Q, and T314T) in 116 healthy individuals from a population-based cohort with at least three generations of Canary Islands’ ancestry are evaluated. The variants were analyzed by SNaPshot. Results Fifty per cent of the population showed at least one phenotypic risk factor (fair skin, 34.3%; freckling, 17.4%; green or blue eyes, 16.8%; red or blonde hair, 7.8%), although brown skin (65.7%), dark eyes (83.2%), and dark hair (92.2%) prevailed. Forty-three per cent of the individuals showed at least one of the MC1R variants studied. Allelic frequencies for V60L, D84E, R150C, R160W, R163Q, and T314T were 9.1%, 1.7%, 3.0%, 0.8%, 3.0%, and 8.2%, respectively. Conclusion A significant proportion of the population showed risk factors for skin cancer. The inhabitants of the Canary Islands are phenotypically and genotypically close to Mediterranean populations.

Experienced forensic pathologists and examiners may be familiar with the phenomenon of postmortem iris color change; however, only Knight, Simpson's forensic medicine, Arnold, London, 1997; Ref. 1 and Saukko and Knight, Knight's forensic pathology, 3rd ed., Arnold, London, 2004; Ref. 2 have referred to it in the literature, and to date, there have been no published scientific research studies on this taphonomic artifact. A controlled experiment was conducted of postmortem changes to isolated Sus scrofa eyes. The eyes (n = 137) were separated into three groups and each sample was observed for 3-day postmortem at a different temperature. In addition, a Sus scrofa head was obtained to observe postmortem changes of eyes in situ. All isolated blue eyes in the experiment, at room temperature and higher, changed to brown/black within 48 h. The in situ blue eye, at room temperature, turned brown/black within 72 h. If iris color consistently changes postmortem in humans, then this taphonomic artifact must be incorporated into victim identification protocol, including disaster victim identification software, and autopsy reports to prevent inaccurate victim identification and inappropriate exclusion from the identification process.

Routine ophthalmoscopy and fundoscopy of 673 individuals revealed 42 whose irides failed to dilate to a clinically useful degree within 25 to 30 min after the administration of drops of 1% mydracil. These individuals occurred with different frequency among the Aymara, Mestizo, and non-Aymara groups which made up the sample of examinees. The phenomenon was most common among the Aymara, less common among the Mestizos, and least common among the non-Aymara. Distribution of affected individuals within the three groups suggests that the trait is inherited.

Three unrelated families (two Jewish and one Druze) are reported, in which a total of eight males exhibited the ophthalmological findings of primary retinal dysplasia. Since our affects male members only have eye findings, this disorder is readily differentiated from Norrie's disease in which other parts of the nervous system are involved. The family pedigrees along with the clinical features support an X-linked recessive mode of transmission for this condition. Female carriers for this gene may show varying types of retinal fold changes. In addition, most of these same presumed female carriers also demonstrated changes in the stroma of their irides, resulting in a gray to grayish-blue color. At present, it is not possible to state definitely whether or not this latter observation is a feature of the carrier state.

Minimal pigment, a new type of oculocutaneous albinism (OCA), is described. At birth, affected individuals had no skin or eye pigment, and white hair and blue irides, but minimal amounts of pigment developed in the iris during the first decade of life. They had no measurable hairbulb tyrosinase activity. A characteristic and unusual pattern of parental activity was found in each of three families studied, with one parent having normal and the other parent having abnormally low tyrosinase activity. The melanocyte ultrastructure was normal and variations in premelanosomal pigmentation correlated with tyrosinase activity. This clinical and biochemical pattern has not been seen in any of the previously described types of OCA. The biochemical defect in minimal pigment OCA is unknown.

Variance in iris color is related to the incidence of several important ocular diseases, including uveal melanoma and age-related macular degeneration. The purposes of this study were to determine the quantity and the types of melanin in cultured human uveal melanocytes in relation to the iris color. Sixty-one cell cultures of pure uveal melanocytes were isolated from donor eyes with various iris colors. The amount of eumelanin (EM) and pheomelanin (PM) of these cells was measured by chemical degradation and microanalytical high-performance liquid chromatography (HPLC) methods. The total amount of melanin was measured by both microanalytical methods and spectrophotometry. Total melanin content, measured by HPLC and spectrophotometry, correlated well with r = 0.872 (P 0.05). When cells became senescent, the levels of EM, PM and total melanin were significantly increased. In both growing and senescent melanocytes, the quantity and type of melanin were closely correlated to the iris color. In cells from eyes with dark-colored irides (dark brown and brown), the amount of EM, the ratio of EM/PM and total melanin were significantly greater than that from eyes with light-colored irides (hazel, green, yellow-brown and blue) (P 0.05). The present study shows that iris color is determined by both the quantity and the type of melanin in uveal melanocytes. These results suggest a possibility that uveal melanin in eyes with dark-colored irides is eumelanic at the surface and acts as an antioxidant while that in eyes with light-colored irides exposes pheomelanic core and behaves as a pro-oxidant.

Objectives (1) To review the signalment, clinical, and histological features of canine limbal melanoma; (2) to perform pedigree analysis on breeds predisposed to limbal melanoma to establish if common ancestry exists; and (3) to investigate if any ancestral relationship exists between canine limbal melanoma and canine anterior uveal melanoma (CAUM). Design Retrospective study. Animals studied Thirty dogs with limbal melanoma. Methods Medical records of patients were reviewed. Follow-up information was obtained by re-examination of patients or telecommunications with the referring veterinary surgeons or the owners. Pedigrees were analyzed for common ancestry amongst affected dogs. Results The mean age (± SD) at diagnosis was 6.2 (± 2.75) years with a range from 1 to 11 years. There was a bimodal distribution of ages with a peak at 3–4 years and a peak at 7–10 years. There was no eye predilection or predisposition for sex or coat color. Twenty-five (83%) of the limbal melanomas occurred within a dorsal arc from the dorsomedial to the ventrolateral limbus. Golden retrievers were four times more common in the melanoma group compared to the Animal Health Trust population (P

Although benign and atypical moles are considered key melanoma risk factors, previous studies of their influence were small and/or institution-based. We conducted a population-based case-control study in the state of New Hampshire. Individuals of ages 20–69 with an incident diagnosis of first primary cutaneous melanoma were ascertained through the New Hampshire State Cancer Registry. Controls were identified through New Hampshire driver's license lists and frequency-matched by age and gender to cases. We interviewed 423 eligible cases and 678 eligible controls. Host characteristics, including mole counts, were evaluated using logistic regression analyses. Our results showed that pigmentary factors, including eye color (OR = 1.57 for blue eyes compared to brown), hair color (OR = 1.85 for blonde/red hair color compared to brown/black), freckles before age 15 (OR = 2.39 for freckles present compared to absent) and sun sensitivity (OR = 2.25 for peeling sunburn followed by no tan or a light tan and 2.42 for sunburn followed by tan compared to tanning immediately), were related to melanoma risk; these associations held after adjustment for sun-related factors and for moles. In analyses confined to skin examination participants, the covariate-adjusted effects of benign and atypical moles were moderately strong. Compared to 0–4 benign moles, risk increased steadily for 5–14 moles (OR = 1.71), 15–24 moles (OR = 3.55) and ≥ 25 moles (OR = 4.33). Risk also increased with the number of atypical moles; compared to none, the ORs for having 1, 2–3, or ≥ 4 atypical moles were 2.08, 1.84 and 3.80, respectively. Although risk was highest for those with multiple benign and atypical moles, the interaction was not of statistical significance. Our findings, arising from the first population- and incidence-based study to evaluate atypical moles in relation to melanoma risk, confirm the importance of host susceptibility, represented by pigmentary factors and the tendency to develop benign or atypical moles, in the etiology of this disease. © 2005 Wiley-Liss, Inc.

The ideal cycloplegic drug that is safe, effective and convenient in children is not yet available. This study aimed to evaluate the safety and efficacy of three cycloplegic regimens in hyperopic children with pigmented irides. The responses to cycloplegia in different age groups and presence of strabismus were also compared.Tropicamide 0.5% and phenylephrine 0.5% (regimen I), tropicamide 1.0% and cyclopentolate 1.0% (regimen II), and atropine 1.0% (regimen III) were evaluated in 25 children using a crossover study design. Cycloplegic refractions were assessed.The mean age of the children was 5.7 +/- 2.0 years (range 2.5-10.8 years). Six (24.0%) of them had strabismus. The spherical equivalent (SE) refraction for regimens I, II and III were +5.11 +/- 2.04 D, +5.29 +/- 1.89 D and +5.71 +/- 1.90 D, respectively, and were significant different from the manifest SE (+3.95 +/- 2.17 D) (P0.001). There was no statistical difference between regimen I and II in children without strabismus (P = 0.258) or aged older than 5 years (P0.050).In older children, regimen I was as effective as regimen II and can be used to avoid cyclopentolate toxicity.