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Purpose Achromatopsia (ACHM) is a congenital, autosomal recessive retinal disease that manifests cone dysfunction, reduced visual acuity and color vision, nystagmus, and photoaversion. Five genes are known causes of ACHM. The present study took steps toward performing a trial of gene therapy in ACHM by characterizing the genetics of ACHM in Israel and the Palestinian Territories and analyzing retinal function and structure in CNGA3 ACHM patients from the Israeli–Palestinian population and US patients with other origins. Design Case series study. Participants Patients with clinically suspected ACHM, cone dysfunction phenotypes, and unaffected family members were included. The protocol was approved by the local institutional review board and informed consent was obtained from all participants. Methods Genetic analyses included homozygosity mapping and exome sequencing. Phenotype was assessed with electroretinography (ERG), optical coherence tomography, psychophysics, and photoaversion testing. Main Outcome Measures Single nucleotide polymorphism microarray, exome analysis, DNA sequence analysis, visual function testing including ERG, and photoaversion. Results We identified 148 ACHM patients from 57 Israeli and Palestinian families; there were 16 CNGA3 mutations (5 novel) in 41 families and 5 CNGB3 mutations (1 novel) in 8 families. Two CNGA3 founder mutations underlie >50% of cases. These mutations lead to a high ACHM prevalence of ∼1:5000 among Arab-Muslims residing in Jerusalem. Rod ERG abnormalities (in addition to cone dysfunction) were detected in 59% of patients. Retinal structure in CNGA3 ACHM patients revealed persistent but abnormal foveal cones. Under dark- and light-adapted conditions, patients use rod-mediated pathways. Photoaversion was readily demonstrated with transition from the dark to a dim light background. Conclusions Among Israeli and Palestinian patients, CNGA3 mutations are the leading cause of ACHM. Retinal structural results support the candidacy of CNGA3 ACHM for clinical trials for therapy of cone photoreceptors. Efficacy outcome measures would include chromatic light-adapted psychophysics, with attention to the photoreceptor basis of the response, and quantitation of photoaversion.

Objectives To present our accumulated data on prenatal molecular diagnosis of oculocutaneous albinism (OCA) in a large cohort of Israeli albino families. Methods Albinism consists of variable phenotypes, but only families with predicted severely handicapped albino offspring, who declared their wish to terminate a pregnancy of such a fetus, are eligible for prenatal testing. Prenatal testing is not offered otherwise. Following detailed genetic investigation and counseling, molecular prenatal testing was performed using the combination of mutation screening, direct sequencing, and haplotype analysis. Results A total of 55 prenatal tests were performed in 37 families; in 26 families the propositus was the child, and in 11, a parent or a close relative. In 32 families tyrosinase (TYR) mutations were diagnosed. In 5 families a P gene mutation was detected. Twelve albino fetuses were diagnosed. Following further genetic counseling, all couples elected to terminate the pregnancy. Three additional pregnancies were terminated for other reasons. Conclusions Families with increased risk for an albino child with severe visual handicap, seek premarital and prenatal genetic counseling and testing, for the prevention of affected offspring. Our combined methods of molecular genetic testing enable a nationwide approach for prevention of albinism. The same paradigm can be applied to other populations affected with albinism. Copyright © 2009 John Wiley & Sons, Ltd.

Achromatopsia (ACHM) is a congenital, autosomal recessive retinal disease that manifests cone dysfunction, reduced visual acuity and color vision, nystagmus, and photoaversion. Five genes are known causes of ACHM. The present study took steps toward performing a trial of gene therapy in ACHM by characterizing the genetics of ACHM in Israel and the Palestinian Territories and analyzing retinal function and structure in CNGA3 ACHM patients from the Israeli-Palestinian population and US patients with other origins.Case series study.Patients with clinically suspected ACHM, cone dysfunction phenotypes, and unaffected family members were included. The protocol was approved by the local institutional review board and informed consent was obtained from all participants.Genetic analyses included homozygosity mapping and exome sequencing. Phenotype was assessed with electroretinography (ERG), optical coherence tomography, psychophysics, and photoaversion testing.Single nucleotide polymorphism microarray, exome analysis, DNA sequence analysis, visual function testing including ERG, and photoaversion.We identified 148 ACHM patients from 57 Israeli and Palestinian families; there were 16 CNGA3 mutations (5 novel) in 41 families and 5 CNGB3 mutations (1 novel) in 8 families. Two CNGA3 founder mutations underlie50% of cases. These mutations lead to a high ACHM prevalence of ∼1:5000 among Arab-Muslims residing in Jerusalem. Rod ERG abnormalities (in addition to cone dysfunction) were detected in 59% of patients. Retinal structure in CNGA3 ACHM patients revealed persistent but abnormal foveal cones. Under dark- and light-adapted conditions, patients use rod-mediated pathways. Photoaversion was readily demonstrated with transition from the dark to a dim light background.Among Israeli and Palestinian patients, CNGA3 mutations are the leading cause of ACHM. Retinal structural results support the candidacy of CNGA3 ACHM for clinical trials for therapy of cone photoreceptors. Efficacy outcome measures would include chromatic light-adapted psychophysics, with attention to the photoreceptor basis of the response, and quantitation of photoaversion.

Achromatopsia is an autosomal recessive disease of the retina, characterized clinically by an inability to distinguish colors, impaired visual acuity, nystagmus and photophobia. A genome-wide search for linkage was performed using an inbred Jewish kindred from Iran. To facilitate the genome-wide search, we utilized a DNA pooling strategy which takes advantage of the likelihood that the disease in this inbred kindred is inherited by all affected individuals from a common founder. Equal molar amounts of DNA from all affected individuals were pooled and used as the PCR template for short tandem repeat polymorphic markers (STRPs). Pooled DNA from unaffected members of the kindred was used as a control. A reduction in the number of alleles in the affected versus control pool was observed at several loci. Upon genotyping of individual family members, significant linkage was established between the disease phenotype and markers localized on chromosome 2. The highest LOD score observed was 5.4 (theta = 0). When four additional small unrelated families were genotyped, the combined peak LOD score was 8.2. Analysis of recombinant chromosomes revealed that the disease gene lies within a 30 cM interval which spans the centromere. Additional fine-mapping studies identified a region of homozygosity in all affected individuals, narrowing the region to 14 cM. A candidate gene for achromatopsia was excluded from this disease interval by radiation hybrid mapping. Linkage of achromatopsia to chromosome 2 is an essential first step in the identification of the disease-causing gene.

We describe molecular prenatal diagnosis and carrier detection of tyrosinase-negative oculocutaneous albinism (OCA1A) in two families. In one family, we carried out DNA-based prenatal diagnosis of OCA1A. In the other family, mutation analysis and carrier detection obviated the need for prenatal diagnosis. Molecular analysis is safer and probably more accurate than fetoscopy and fetal scalp biopsy, and should become the method of first choice for prenatal diagnosis of OCA1.

Purpose To evaluate the prevalence of refractive errors in different subtypes of oculocutaneous albinism, and to see if there is any correlation between refractive errors and final visual outcome in this population. Patients/methods This is a retrospective study of 132 albino patients, ranging in age from 0.5 to 35 years. They were divided into four subtypes: OCA1A, OCA1B and OCA1C, and OCA2. Refractive errors were evaluated objectively by cycloplegic refraction and subjectively in cooperative patients. Best corrected visual acuity was assessed binocularly. Refractive errors were divided into three groups—hypermetropia, myopia and astigmatism—to avoid the use of spherical equivalent. Results Refractive errors were mainly astigmatism and hypermetropia. The OCA1A group showed high hypermetropia (≥5 dioptres) in 43.4% of patients, reaching significantly higher levels than in other subgroups (p=0.007). Mean visual acuity in logMAR was: OCA1A=0.81, OCA1B=0.64, OCA1C=0.61 and OCA2=0.48. Astigmatism averaged 2.1 dioptres (consistently with-the-rule), and it was homogeneously distributed between all subgroups (53%). Conclusions The poorest visual acuity was found in those with OCA1A, which was associated with the highest rate of high hypermetropia (statistically significant different from other subgroups). Astigmatism was the most common visually significant refractive error across all subtypes of albinism. These results may help to clarify the prevalence of refractive errors in albino patients and aid the prediction of visual outcome in this heterogeneous population.

PURPOSE. To clinically characterize and genetically analyze members of six families who reside in the same village and manifest a rare form of retinal degeneration. METHODS. Ophthalmic evaluation included a full clinical examination, perimetry, color vision testing, and electroretinography. Genomic DNA was screened for ABCA4 mutations with the use of microarray analysis and direct sequencing. RNA analysis was performed with RT-PCR and sequencing. RESULTS. The authors recruited 15 patients with a unique retinal disease who are members of six highly consanguineous Arab-Muslim families from a single village. During early stages of disease, funduscopic and angiographic findings as well as retinal function resemble those of Stargardt disease. However, later in life, severe, widespread cone-rod degeneration ensues. Marked progressive involvement of the retinal periphery distinguishes this phenotype from classic Stargardt disease. Genetic analysis of ABCA4 revealed two novel deletions, p.Cys1150del and c.4254-15del23. One patient, who was a compound heterozygote, manifested typical Stargardt disease. The remaining 14 patients were homozygote for the c.4254-15del23 intronic deletion and had the progressive form of disease. We identified an identical ABCA4 haplotype in all alleles carrying this mutation, indicating a founder mutation. Detailed RT-PCR analysis in normal retina and lymphoblastoid cells revealed expression of the full-length ABCA4 transcript and three novel transcripts produced by alternative splicing. The full-length ABCA4 transcript, however, could not be detected in lymphoblastoid cells of affected homozygote patients. CONCLUSIONS. These results expand the genotype-phenotype correlation of ABCA4, showing that homozygosity for the novel c.4254-15de1l3 splicing mutation is associated with a severe progressive form of disease.

An extended, highly consanguineous Israeli Bedouin family with at least 20 individuals exhibiting a unique phenotype of oculocutaneous albinism (OCA) was identified. All known OCA genes were excluded in this family. Electron microscopic analysis of platelets revealed absence of dense bodies, suggesting a diagnosis of Hermansky-Pudlak syndrome (HPS). HPS is a rare autosomal recessive disorder of lysosome-related organelle biogenesis, clinically characterized by OCA and platelet dysfunction, sometimes accompanied by other systemic pathologies. All human HPS genes (HPS1-8) and five genes corresponding to murine HPS models were evaluated. Haplotype analysis and homozygosity mapping of the HPS loci revealed linkage to chromosome 10 in the studied family. Subsequently, a novel insertion mutation, c.1066-1067insG was identified in HPS6. Most frameshift mutations generating premature termination codon cause mRNA nonsense mediated decay (NMD), while intronless genes like HPS6 are usually not monitored by NMD. Expression analysis revealed no mRNA decay in patient's fibroblasts, hence truncated protein is most probably produced. Confocal microscopy revealed abnormal distribution of LAMP-3 (lysosomal associated membrane protein-3) in fibroblasts from the patients, indicating abnormal trafficking of lysosomal lineage organelles. So far, a single HPS-6 patient phenotypically similar to HPS-3 and HPS-5 has been identified. The HPS-6 phenotype in the studied family is unique since it resembles OCA and not HPS. Therefore, our finding broadens the phenotypic definition of HPS. Two major genetic isolates of HPS-1 and HPS-3 patients were previously diagnosed in Puerto Rico. The extended Bedouin family is the largest isolate of non-Puerto Rican HPS patients. Published 2006 Wiley-Liss, Inc.

Oculocutaneous albinism type I (OCA I) comprises autosomal recessive syndromes of hypopigmentation and low vision, caused by the lack of tyrosinase activity. Affected families seek genetic counseling and prenatal diagnosis as preventive measures. Until recently, prenatal diagnosis of OCA I was achieved by histologic and electron microscopic examination of fetal skin biopsies. Lately, a molecular genetic approach has become possible by the identification of the two mutated copies of the TYR gene, coding the tyrosinase, in which over 60 mutations have been identified. We report here our experience in prenatal diagnosis of OCA I using the two strategies. Thirty-four prenatal tests were performed in fetuses at risk for OCA I. In 31 cases the diagnosis was made in fetal scalp biopsies using the histological approach. The microscopic observations revealed normal melanogenesis in 26 biopsies. Five albino fetuses were diagnosed by the demonstration of arrest of melanogenesis in early stages I and II. In three pregnancies, molecular genetic tests were performed on DNA extracted from amniocytes, using direct mutation analysis (in one), and complemented by linkage analysis (in two). One albino and two normally pigmented fetuses were diagnosed. The prenatal molecular genetic test can be applied to families when at least one mutation is diagnosed in the albino patient. The histological approach is applicable in all families at risk for OCA I.

We have investigated a family with one child affected with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Prenatal determination of 17-α hydroxyprogesterone (17OHP) in amniotic fluid (AF) and HLA typing of amniotic fibroblasts from a pregnancy at risk showed that the fetus was not affected. A healthy cousin with HLA haplotypes identical to those of the proposita (only one being identical by descent) had a normal plasma level of 17OHP. The prenatal diagnosis of a fetus affected with 21-hydroxylase deficiency CAH may be established by the determination of 17OHP in AF. This is a relatively quick procedure that can be confirmed by the HLA genotype, and is mandatory in families with a parent homozygous for an HLA haplotype and in certain recombinant haplotypes in the fetus.

Müllerian duct derivatives were identified in an infertile adult male patient who had long-standing azoospermia and was operated on for inguinal hernia. Persistent müllerian duct syndrome is reviewed, with special emphasis on the pathophysiologic and surgical considerations involved in the treatment of this abnormality.

To predict 11β-hydroxylase deficiency congenital adrenal hyperplasia antenatally, studies were performed in urines and amniotic fluids from 2 pregnant women who had previously given birth to affected infants and whose present pregnancies also resulted in infants with the disease. Urinary tetrahydro-11-deoxycortisol [pregnane-3α, 17α, 21-triol-20-one (THS)] was abnormally elevated in the first, second, and third trimesters (maximal values, 3.5 and 0.9 mg/24 h, respectively) but was undetectable after delivery in these mothers, in 15 normal pregnancies (10–40 weeks of gestation), and in 6 heterozygote parents. Amniotic fluid levels of THS, tetrahydrocortisol [pregnane-3α, 11β, 17α, 21-tetra-ol-20-one (THF)], tetrahydrocortisone [pregnane-3α, 17α, 21-triol-ll, 20-dione (THE)] measured by RIA at 18 weeks of gestation in the first mother and at 40 weeks in the second revealed 12.5- and 8.4-fold increases in THS, respectively, but normal THF and THE levels compared t o mean levels in normal pregnancies. The THS...

Amniotic fluid rT3 levels were measured during pregnancy in two women who previously gave birth to infants suffering from neonatal hypothyroidism. In the first case, hypothyroidism was strongly suspected because of repeated low levels of rT3 in the amniotic fluid (20-64 ng/dl) at 16 and 31 weeks of gestation. A normal infant was delivered. He is now 10 months old and taking no treatment; he has no clinical or laboratory signs of hypothyroidism. In the second case, amniotic rT3 levels (140-180 ng/dl) were well within the normal range for 15-19 weeks of pregnancy, but an affected hypothyroid infant was born. These data suggest that amniotic fluid rT3 levels may not be a reliable tool in diagnosing intrauterine hypothyroidism.

A patient with the clinical stigmata of gonadal dysgenesis is presented. Cytogenetic investigations revealed two distinct structural chromosome rearrangements. One of these, an isochromosome for the long arm of the X, proved to be a dicentric element following C-banding. The second abnormality, an inherited familial marker, was a pericentric inversion of No. 2 {(inv 2) (p15) q21).

An 18 year old phenotypic man is described with chromatin-positive Klinefelter's syndrome and undetectable peripheral human follicle stimulating hormone levels. The subject manifested chromosomal mosaicism consisting of three stem cell lines (45X; 46XY; and 47XXY). Testicular biopsy specimen showed germinal cell aplasia: the tubules were lined by Sertoli cells only, whereas the Leydig cells appeared normal. Serum human follicle stimulating hormone levels were undetectable and rose to only 5 mIU/ml after the administration of luteinizing hormone releasing hormone. Serum human luteinizing hormone varied between normal and moderately elevated values, and serum testosterone was in the low normal range. We discuss the features which distinguish this syndrome from isolated gonadotropin deficiency and from classic germinal cell aplasia. We suggest that the patient represents a new variant of Klinefelter's syndrome, with failure of human follicle stimulating hormone release secondary to prolonged hypersecretion.

The mean control level of 11-deoxycortisol as determined by radioimmunoassay in eighty-one human amniotic fluid samples was 1.20 +/- 0.07 ng/ml. Markedly elevated levels were found at term in amniotic fluid of two pregnancies with fetuses affected with 11 beta-hydroxylase deficiency, congenital adrenal hyperplasia (135.0 and 64.0 ng/ml respectively) as well as in the maternal serum of one of these cases (28.0 ng/ml). It is suggested that the determination of 11-deoxycortisol in amniotic fluid be a prenatal diagnostic test for 11 beta-hydroxylase deficiency congenital adrenal hyperplasia.