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We report a case of Albright hereditary osteodystrophy (AHO) in a three-year-old girl with a microduplication at 17q11.2. The child developed obesity within the first 6 months of life. A diagnosis of Albright was made at age 2 years when biochemical evidence of parathyroid resistance was found. No mutations were identified in guanine nucleotide-binding protein G (s) subunit alpha (GNAS1). Subsequent investigations revealed methylation disturbance at GNAS1A, neuroendocrine secretory protein antisense (NESPAS) and neuroendocrine secretory protein 55 (NESP55) confirming a diagnosis of pseudohypothyroidism type 1B. A deletion of NESP55 and uniparental disomy chromosome 20 were excluded which suggested that the features of AHO arose through a purely epigenetic mechanism. Further investigation revealed a de novo microduplication at 17q11.2 encompassing the neurofibromatosis type 1 (NF1) gene. The combination of two rare de novo events in the same child raises the possibility that duplication of a gene within the 17q11.2 region may have triggered abnormal methylation in the GNAS cluster region on chromosome 20.

Significant mortalities of the Pacific oyster, Crassostrea gigas, have been reported worldwide since the 1950s. The impact these re-occurring mortality events have had on the C. gigas industry has highlighted the necessity to determine the factors that may be causing these mortalities. This study investigated the possible role of ostreid herpes virus (OsHV-1) in C. gigas mortalities over 2 successive summers at 2 study areas in Ireland. A single sample of adult C. gigas, which had been experiencing mortalities at one of the sites was screened. Successive cohorts of C. gigas spat obtained from a hatchery outside Ireland was relayed to both sites in 2003 and in 2004. Spat were screened each year prior to relaying. Samples were collected every 2 weeks and mortality counts were recorded and observed at both sites. Polymerase chain reaction (PCR) analysis and subsequent sequencing indicated that a previously undocumented variant genotype of OsHV-1 was present in the single cohort of adult C. gigas and in seed and juveniles at both sites, in both years. Analysis suggests that the Irish OsHV-1 μvar variant genotype is closely related to OsHV-1 μvar, first described in France in 2008.

Coffin-Siris syndrome (CSS) is a rare, clinically heterogeneous disorder often considered in the setting of cognitive/developmental delay and 5th finger/nail hypoplasia. Due to the clinical variability of facial and other features, this diagnosis is often difficult to confirm clinically and the existence of this disorder as a specific diagnosis has been at times an issue of debate. In an effort to further delineate the spectrum and key phenotypic features, we reviewed 80 previously reported cases to define features in patients that most closely correlated with a convincing diagnosis. There appear to be two subtypes of CSS, one which displays the "classic" coarse facial features previously described; another displays "variant" facial features which are less striking. Using these features, we defined an algorithm to rank the confidence of diagnosis and applied it to 15 additional patients who had been previously characterized by chromosome microarray. This approach will also facilitate uniform categorization for whole-exome analysis., (Copyright © 2012 Wiley Periodicals, Inc.)

We present two brothers with mutations in UPF3B, an X-linked intellectual disability gene. Our family consists of two affected brothers and a carrier mother. Both affected brothers had renal dysplasia. A maternal uncle died from a congenital heart defect at 4 months. The two boys had variable degrees of developmental delay. One had macrocephaly, significant expressive speech delay and constipation. The other brother had normocephaly, obsessional tendencies and was diagnosed with high functioning autism. The phenotypically normal mother had 100% skewed X-inactivation. Our cases expand the phenotype seen with UPF3B mutations and highlight the variability within families., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

The evolutionarily conserved cohesin complex was originally described for its role in regulating sister-chromatid cohesion during mitosis and meiosis. Cohesin and its regulatory proteins have been implicated in several human developmental disorders, including Cornelia de Lange (CdLS) and Roberts syndromes. Here we show that human mutations in the integral cohesin structural protein RAD21 result in a congenital phenotype consistent with a "cohesinopathy." Children with RAD21 mutations display growth retardation, minor skeletal anomalies, and facial features that overlap findings in individuals with CdLS. Notably, unlike children with mutations in NIPBL, SMC1A, or SMC3, these individuals have much milder cognitive impairment than those with classical CdLS. Mechanistically, these mutations act at the RAD21 interface with the other cohesin proteins STAG2 and SMC1A, impair cellular DNA damage response, and disrupt transcription in a zebrafish model. Our data suggest that, compared to loss-of-function mutations, dominant missense mutations result in more severe functional defects and cause worse structural and cognitive clinical findings. These results underscore the essential role of RAD21 in eukaryotes and emphasize the need for further understanding of the role of cohesin in human development., (Copyright © 2012 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

The advancement of synthetic biology is thanks, in large part, to continuing improvements in DNA synthesis. The expansion of synthetic biology into the realm of metabolic engineering has shifted the focus from simply making novel synthetic biological parts to answering the question of how we employ these biological parts to construct genomes that ultimately give rise to useful phenotypes. Much like protein engineering, the answer to this will be arrived at following the combination of rational design and evolutionary approaches. This review will highlight some of the new DNA synthesis-enabled search methods and discuss the application of such methods to the creation of synthetic gene networks and genomes., (Copyright © 2012 Elsevier Inc. All rights reserved.)

MLL2 mutations are detected in 55 to 80% of patients with Kabuki syndrome (KS). In 20 to 45% patients with KS, the genetic basis remains unknown, suggesting possible genetic heterogeneity. Here, we present the largest yet reported cohort of 116 patients with KS. We identified MLL2 variants in 74 patients, of which 47 are novel and a majority are truncating. We show that pathogenic missense mutations were commonly located in exon 48. We undertook a systematic facial KS morphology study of patients with KS at our regional dysmorphology meeting. Our data suggest that nearly all patients with typical KS facial features have pathogenic MLL2 mutations, although KS can be phenotypically variable. Furthermore, we show that MLL2 mutation-positive KS patients are more likely to have feeding problems, kidney anomalies, early breast bud development, joint dislocations and palatal malformations in comparison with MLL2 mutation-negative patients. Our work expands the mutation spectrum of MLL2 that may help in better understanding of this molecule, which is important in gene expression, epigenetic control of active chromatin states, embryonic development and cancer. Our analyses of the phenotype indicates that MLL2 mutation-positive and -negative patients differ systematically, and genetic heterogeneity of KS is not as extensive as previously suggested. Moreover, phenotypic variability of KS suggests that MLL2 testing should be considered even in atypical patients.

The objective of this study was to examine whether preoperative recommendation for specific reductions in body mass index (BMI) influenced weight loss in obese surgical patients. We retrospectively reviewed the electronic medical records of 48 patients who enrolled between January 2007 to June 2010 in an 800-calorie per day liquid meal replacement (LMR) weight loss program. Of these, 9 patients (surgical group) enrolled as a result of general surgeon-directed weight loss to enable nonbariatric surgery and 39 enrolled seeking weight loss (medical group). Patients enrolled in the LMR program before bariatric surgery were excluded from analysis. All patients were seen in the setting of a comprehensive weight loss program supervised by a medical bariatrician and followed for a period of 4 months. There were no significant differences in mean initial BMI between surgical and medical patients (41.7 ± 4.55 and 41.6 ± 8.54 kg/m(2), respectively) or participation time in the weight loss program (120 days vs 133 days). Of the nine surgical patients, only five (56%) reached their weight goal and underwent the planned surgical procedure. Weight loss was significantly less in the surgical compared with medical patients (BMI reduction 4.03 ± 3.99 vs 7.75 ± 4.90 kg/m(2), respectively; P < 0.05). Weight loss was significantly lower in patients directed to undergo BMI reduction to enable a general surgical procedure. Future studies are needed to assess factors influencing weight loss (metabolism, exercise capacity, motivation) in patients requiring weight loss to enable a surgical procedure.

Background: Germline mutations in the CHRNG gene that encodes the γ subunit of the embryonal acetylcholine receptor may cause the non-lethal Escobar variant (EVMPS) or the lethal form (LMPS) of multiple pterygium syndrome (MPS). In addition CHRNG mutations and mutations in other components of the embryonal acetylcholine receptor may present with fetal akinesia deformation sequence (FADS) without pterygia., Methods: In order to elucidate further the role of CHRNG mutations in MPS/FADS, this study evaluated the results of CHRNG mutation analysis in 100 families with a clinical diagnosis of MPS/FADS., Results: CHRNG mutations were identified in 11/41 (27%) of families with EVMPS and 5/59 (8%) with LMPS/FADS. Most patients with a detectable CHRNG mutation (21 of 24 (87.5%)) had pterygia but no CHRNG mutations were detected in the presence of central nervous system anomalies., Discussion: The mutation spectrum was similar in EVMPS and LMPS/FADS kindreds and EVMPS and LMPS phenotypes were observed in different families with the same CHRNG mutation. Despite this intrafamilial variability, it is estimated that there is a 95% chance that a subsequent sibling will have the same MPS phenotype (EVMPS or LMPS) as the proband (though concordance is less for more distant relatives). Based on these findings, a molecular genetic diagnostic pathway for the investigation of MPS/FADS is proposed.

Say-Barber-Biesecker-Young-Simpson syndrome (SBBYSS or Ohdo syndrome) is a multiple anomaly syndrome characterized by severe intellectual disability, blepharophimosis, and a mask-like facial appearance. A number of individuals with SBBYSS also have thyroid abnormalities and cleft palate. The condition usually occurs sporadically and is therefore presumed to be due in most cases to new dominant mutations. In individuals with SBBYSS, a whole-exome sequencing approach was used to demonstrate de novo protein-truncating mutations in the highly conserved histone acetyltransferase gene KAT6B (MYST4/MORF)) in three out of four individuals sequenced. Sanger sequencing was used to confirm truncating mutations of KAT6B, clustering in the final exon of the gene in all four individuals and in a further nine persons with typical SBBYSS. Where parental samples were available, the mutations were shown to have occurred de novo. During mammalian development KAT6B is upregulated specifically in the developing central nervous system, facial structures, and limb buds. The phenotypic features seen in the Qkf mouse, a hypomorphic Kat6b mutant, include small eyes, ventrally placed ears and long first digits that mirror the human phenotype. This is a further example of how perturbation of a protein involved in chromatin modification might give rise to a multisystem developmental disorder., (Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

We report eight unrelated individuals with intellectual disability and overlapping submicroscopic deletions of 8q21.11 (0.66-13.55 Mb in size). The deletion was familial in one and simplex in seven individuals. The phenotype was remarkably similar and consisted of a round face with full cheeks, a high forehead, ptosis, cornea opacities, an underdeveloped alae, a short philtrum, a cupid's bow of the upper lip, down-turned corners of the mouth, micrognathia, low-set and prominent ears, and mild finger and toe anomalies (camptodactyly, syndactyly, and broadening of the first rays). Intellectual disability, hypotonia, decreased balance, sensorineural hearing loss, and unusual behavior were frequently observed. A high-resolution oligonucleotide array showed different proximal and distal breakpoints in all of the individuals. Sequencing studies in three of the individuals revealed that proximal and distal breakpoints were located in unique sequences with no apparent homology. The smallest region of overlap was a 539.7 kb interval encompassing three genes: a Zinc Finger Homeobox 4 (ZFHX4), one microRNA of unknown function, and one nonfunctional pseudogen. ZFHX4 encodes a transcription factor expressed in the adult human brain, skeletal muscle, and liver. It has been suggested as a candidate gene for congenital bilateral isolated ptosis. Our results suggest that the 8q21.11 submicroscopic deletion represents a clinically recognizable entity and that a haploinsufficient gene or genes within the minimal deletion region could underlie this syndrome., (Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Background: Anomalies of dental anatomy are common in the ectodermal dysplasia syndromes. These anomalies, when found in combination with dental caries, can pose a restorative challenge for the paediatric dentist. Modification of traditional techniques and approaches may help the practitioner provide a successful treatment outcome., Case Report: A 3 years and 11 months old girl with a diagnosis of ankyloblepharon-ectodermal dysplasiacleft lip/palate (AEC) syndrome was referred for treatment to a specialist paediatric dental service. Her abnormal dental anatomy, hypodontia and dental caries formed a triad of challenges for the team. Under general anaesthesia, her dentition was restored using a combination of restorative approaches and techniques, including the placement of both composite resin and preformed metal crown restorations., Follow-Up: At 18-month followup, the family had successfully implemented good home care and dietary practices, and the local dental service had instituted a preventive programme consisting of regular examination, advice and fluoride varnish placement. The restorations remained intact and no further caries was detected. At 24-month follow-up, the first permanent molars were partially erupted, and displayed unusually deep fissures. There was also a degree of ectopic eruption of the first permanent molars, and possibly of one of the maxillary permanent incisors., Conclusion: Dental care for children with AEC syndrome is optimised by early intervention, good home care and regular professional review. Dental care providers should be aware of the possibility of complex dental anatomy, and bear this in mind should it become necessary to formulate a restorative treatment plan.

Geleophysic (GD) and acromicric dysplasia (AD) belong to the acromelic dysplasia group and are both characterized by severe short stature, short extremities, and stiff joints. Although AD has an unknown molecular basis, we have previously identified ADAMTSL2 mutations in a subset of GD patients. After exome sequencing in GD and AD cases, we selected fibrillin 1 (FBN1) as a candidate gene, even though mutations in this gene have been described in Marfan syndrome, which is characterized by tall stature and arachnodactyly. We identified 16 heterozygous FBN1 mutations that are all located in exons 41 and 42 and encode TGFβ-binding protein-like domain 5 (TB5) of FBN1 in 29 GD and AD cases. Microfibrillar network disorganization and enhanced TGFβ signaling were consistent features in GD and AD fibroblasts. Importantly, a direct interaction between ADAMTSL2 and FBN1 was demonstrated, suggesting a disruption of this interaction as the underlying mechanism of GD and AD phenotypes. Although enhanced TGFβ signaling caused by FBN1 mutations can trigger either Marfan syndrome or GD and AD, our findings support the fact that TB5 mutations in FBN1 are responsible for short stature phenotypes., (Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Background: Geleophysic dysplasia (GD, OMIM 231050) is an autosomal recessive disorder characterised by short stature, small hands and feet, stiff joints, and thick skin. Patients often present with a progressive cardiac valvular disease which can lead to an early death. In a previous study including six GD families, we have mapped the disease gene on chromosome 9q34.2 and identified mutations in the A Disintegrin And Metalloproteinase with Thrombospondin repeats-like 2 gene (ADAMTSL2)., Methods: Following this study, we have collected the samples of 30 additional GD families, including 33 patients and identified ADAMTSL2 mutations in 14/33 patients, comprising 13 novel mutations. The absence of mutation in 19 patients prompted us to compare the two groups of GD patients, namely group 1, patients with ADAMTSL2 mutations (n=20, also including the 6 patients from our previous study), and group 2, patients without ADAMTSL2 mutations (n=19)., Results: The main discriminating features were facial dysmorphism and tip-toe walking, which were almost constantly observed in group 1. No differences were found concerning heart involvement, skin thickness, recurrent respiratory and ear infections, bronchopulmonary insufficiency, laryngo-tracheal stenosis, deafness, and radiographic features., Conclusions: It is concluded that GD is a genetically heterogeneous condition. Ongoing studies will hopefully lead to the identification of another disease gene.

We report six patients with array deletions encompassing 12q14. Out of a total of 2538 array investigations carried out on children with developmental delay and dysmorphism in three diagnostic testing centres, six positive cases yielded a frequency of 1 in 423 for this deletion syndrome. The deleted region in each of the six cases overlaps significantly with previously reported cases with microdeletions of this region. The chromosomal range of the deletions extends from 12q13.3q15. In the current study, we report overlapping deletions of variable extent and size but primarily comprising chromosomal bands 12q13.3q14.1. Four of the six deletions were confirmed as de novo events. Two cases had deletions that included HMGA2, and both children had significant short stature. Neither case had osteopoikilosis despite both being deleted for LEMD3. Four cases had deletions that ended proximal to HMGA2 and all of these had much better growth. Five cases had congenital heart defects, including two with atrial septal defects, one each with pulmonary stenosis, sub-aortic stenosis and a patent ductus. Four cases had moderate delay, two had severe developmental delay and a further two had a diagnosis of autism. All six cases had significant speech delay with subtle facial dysmorphism.

Many children with chronic genetic diseases are followed by specialty clinics that provide genetic information as part of the care. Health services restrictions in the Republic of Ireland (ROI) can make the wait for an appointment with a genetic counsellor long. We examined whether genetic information was being adequately understood when presented by medical, but non-genetics staff to long term patients, using our national metabolic service as an example. The aim was to inform health professionals about the need or role of a genetic counsellor in a specialist setting. A questionnaire was used to assess knowledge among parents and patients affected by galactosaemia and Maple Syrup Urine Disease (MSUD). Twenty seven families with galactosemia and 10 with MSUD were interviewed in clinic. Comparative analysis showed significant differences in knowledge between parents of children with galactosemia and adult patients (p=0.001) and between ethnicities (p>0.05). While parents are well informed, the majority expressed a wish for more information about the condition and its transmission. Adult patients with galactosemia and parents from certain ethnic backgrounds could especially benefit from genetic counselling. This study highlights the need for a genetic counsellor in specialist clinics.

Research towards the commercialization of fungible biofuels has received a great deal of recent interest and investment. To this end the microbial production of fatty acid-derived fuels from sustainable feedstocks is emerging as a viable option with rapid advances from both industry and academia. The manipulation of the fatty acid biosynthesis pathway, especially in Escherichia coli, has been widely studied and several approaches that increase fatty acid production have been identified. However, further advances will be required for the economic large-scale production of fatty acid-derived biofuels. Here we present an overview of fatty acid biosynthesis and its regulation in E. coli from a metabolic engineering viewpoint and offer potential approaches and considerations for the microbial overproduction of custom designed fatty acids for use as biofuels or in the manufacture of oleochemicals., (© 2010 Elsevier Inc. All rights reserved.)

A range of phenotypes including Greig cephalopolysyndactyly and Pallister-Hall syndromes (GCPS, PHS) are caused by pathogenic mutation of the GLI3 gene. To characterize the clinical variability of GLI3 mutations, we present a subset of a cohort of 174 probands referred for GLI3 analysis. Eighty-one probands with typical GCPS or PHS were previously reported, and we report the remaining 93 probands here. This includes 19 probands (12 mutations) who fulfilled clinical criteria for GCPS or PHS, 48 probands (16 mutations) with features of GCPS or PHS but who did not meet the clinical criteria (sub-GCPS and sub-PHS), 21 probands (6 mutations) with features of PHS or GCPS and oral-facial-digital syndrome, and 5 probands (1 mutation) with nonsyndromic polydactyly. These data support previously identified genotype-phenotype correlations and demonstrate a more variable degree of severity than previously recognized. The finding of GLI3 mutations in patients with features of oral-facial-digital syndrome supports the observation that GLI3 interacts with cilia. We conclude that the phenotypic spectrum of GLI3 mutations is broader than that encompassed by the clinical diagnostic criteria, but the genotype-phenotype correlation persists. Individuals with features of either GCPS or PHS should be screened for mutations in GLI3 even if they do not fulfill clinical criteria., (Hum Mutat 31:1142-1154, 2010. © 2010 Wiley-Liss, Inc.)

This study investigated the ability of the Pacific oyster, Crassostrea gigas, to act as a carrier or reservoir of the protistan Bonamia ostreae. Studies were carried out independently in Ireland and in Spain. Naïve C. gigas were exposed to B. ostreae both in the field and in the laboratory via natural exposure or experimental injection. Naïve flat oysters, Ostrea edulis, were placed in tanks with previously exposed C. gigas. Oysters were screened for B. ostreae by examination of ventricular heart smears and by polymerase chain reaction (PCR) screening of tissue samples (gill and/or heart) and shell cavity fluid. PCR-positive oysters were further screened using histology and in situ hybridization (ISH). B. ostreae DNA was detected in the tissues and/or shell cavity fluid of a small number of C. gigas in the field and in the laboratory. B. ostreae-like cells were visualized in the haemocytes of 1 C. gigas and B. ostreae-like cells were observed extracellularly in the connective tissues of 1 other C. gigas. When C. gigas naturally exposed to B. ostreae were held with naïve O. edulis, B. ostreae DNA was detected in O. edulis; however, B. ostreae cells were not visualized. In Spain, B. exitiosa DNA was also detected in Pacific oyster tissues. The results of this study have important implications for C. gigas transfers from B. ostreae-endemic areas to uninfected areas and highlight B. ostreae and B. exitiosa's ability to survive extracellularly and in other non-typical hosts.

Laser cooling and electromagnetic traps have led to a revolution in atomic physics, yielding dramatic discoveries ranging from Bose-Einstein condensation to the quantum control of single atoms. Of particular interest, because they can be used in the quantum control of one atom by another, are excited Rydberg states, where wavefunctions are expanded from their ground-state extents of less than 0.1 nm to several nanometres and even beyond; this allows atoms far enough apart to be non-interacting in their ground states to strongly interact in their excited states. For eventual application of such states, a solid-state implementation is very desirable. Here we demonstrate the coherent control of impurity wavefunctions in the most ubiquitous donor in a semiconductor, namely phosphorus-doped silicon. In our experiments, we use a free-electron laser to stimulate and observe photon echoes, the orbital analogue of the Hahn spin echo, and Rabi oscillations familiar from magnetic resonance spectroscopy. As well as extending atomic physicists' explorations of quantum phenomena to the solid state, our work adds coherent terahertz radiation, as a particularly precise regulator of orbitals in solids, to the list of controls, such as pressure and chemical composition, already familiar to materials scientists.

The objective of the study was to examine the aetiology of sensorineural hearing loss (SNHL) in a paediatric population presenting to the National Centre of Medical Genetics. A retrospective chart review from 1998 to 2006. One hundred and twenty nine children were investigated for SNHL. The average age of diagnosis of hearing loss was 36 months. The degree of hearing loss was mild in 8 children, moderate in 33 children, severe in 31 children and profound in 57 children. Eighty-five children (66%) were diagnosed with a hereditary hearing loss, 11 (8%) children had an acquired hearing loss and no cause found in 33 (26%) children. This is the first report of the causes of hearing loss in Irish children. The mean age of diagnosis in our cohort is high and emphasises the need for a neonatal screening programme. There remains a number of children for whom the cause of hearing loss remains unknown.

BACKGROUND: Interstitial deletions of the long arm of chromosome 6 have been described in several patients with obesity and a Prader-Willi-like phenotype. Haploinsufficiency of the SIM1 gene located at 6q16.3 is suggested as being responsible for the regulation of body weight. Here we report on 2 patients with interstitial deletions at 6q14.1-q15 presenting with obesity and symptoms strikingly similar to those reported for deletions involving the SIM1 gene despite not having a deletion of this gene. METHODS: Array comparative genomic hybridisation was used to diagnose 2 children with obesity and developmental delay, revealing 2 interstitial deletions at 6q14.1-q15 of 8.73 and 4.50 Mb, respectively, and a region of overlap of 4.2-Mb. RESULTS: The similar phenotype in the 2 patients was most likely due to a 4.2-Mb common microdeletion at 6q14.1-q15. Another patient has previously been described with an overlapping deletion. The 3 patients share several features, such as developmental delay, obesity, hernia, rounded face with full cheeks, epicanthal folds, short palpebral fissures, bulbous nose, large ears, and syndactyly between toes II and III. CONCLUSIONS: Together with a previously reported patient, our study suggests that the detected deletions may represent a novel clinically recognisable microdeletion syndrome caused by haploinsufficiency of dosage-sensitive genes in the 6q14.1-q15 region.

Submicroscopic copy-number variations make a considerable contribution to the genetic etiology of human disease. We have analyzed subjects with idiopathic mental retardation (MR) by using whole-genome oligonucleotide-based array comparative genomic hybridization (aCGH) and identified familial and de novo recurrent Xp11.22-p11.23 duplications in males and females with MR, speech delay, and a peculiar electroencephalographic (EEG) pattern in childhood. The size of the duplications ranges from 0.8-9.2 Mb. Most affected females show preferential activation of the duplicated X chromosome. Carriers of the smallest duplication show X-linked recessive inheritance. All other affected individuals present dominant expression and comparable clinical phenotypes irrespective of sex, duplication size, and X-inactivation pattern. The majority of the rearrangements are mediated by recombination between flanking complex segmental duplications. The identification of common clinical features, including the typical EEG pattern, predisposing genomic structure, and peculiar X-inactivation pattern, suggests that duplication of Xp11.22-p11.23 constitutes a previously undescribed syndrome.

Objective: Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disease characterized by isolated glucocorticoid deficiency with preserved mineralocorticoid secretion. Mutations in the ACTH receptor (MC2R) account for approximately 25% of all FGD cases, but since these are usually missense mutations, a degree of receptor function is frequently retained. A recent report, however, suggested that disturbances in the renin-aldosterone axis were seen in some patients with potentially more severe MC2R mutations. Furthermore, MC2R knock out mice have overt aldosterone deficiency and hyperkalaemia despite preservation of a normal zona glomerulosa. We wished to determine whether a group of patients with severe nonsense mutations of the MC2R exhibited evidence of mineralocorticoid deficiency, thereby challenging the conventional diagnostic feature of FGD which might result in diagnostic misclassification., Design: Clinical review of patients with nonsense MC2R mutations., Patients: Between 1993 and 2008, 164 patients with FGD were screened for mutations in the MC2R. Totally 42 patients (34 families) were found to have mutations in the MC2R. Of these, 6 patients (4 families) were found to have homozygous nonsense or frameshift mutations., Results: Mild disturbances in the renin-angiotensin-aldosterone axis were noted in four out of six patients, ranging from slightly elevated plasma renin levels to low aldosterone levels, although frank mineralocorticoid deficiency or electrolyte disturbance were not found. No patient required fludrocortisone replacement., Conclusion: Severe nonsense and frameshift MC2R mutations are not associated with clinically significant mineralocorticoid deficiency and are thus unlikely to require long-term mineralocorticoid replacement.

Background: Bannayan-Riley-Ruvalcaba syndrome (BRRS) is an autosomal dominant condition characterised by macrocephaly, developmental delay and subtle cutaneous features. BRRS results from mutations in the PTEN gene. In adults, PTEN mutations cause Cowden syndrome where, in addition to the macrocephaly, there is a higher risk of tumour development. Diagnosis of BRRS is often delayed as presentation can be variable, even within families., Aims: To identify characteristics of this condition which might facilitate early diagnosis. Prompt diagnosis not only avoids unnecessary investigations in the child but potentially identifies heterozygote parents who are at risk of tumour development., Methods and Results: Six children with a PTEN mutation were identified. All had extreme macrocephaly. Four parents and a male sibling were found to have a PTEN mutation on subsequent testing. Affected parents had extreme macrocephaly and a history of thyroid adenoma, or breast or skin lesions. All six children had presented to medical attention before the age of 2.5 years (3/6 were investigated as neonates), but the median age at diagnosis was 5 years. Four of the children had multiple investigations prior to identification of a PTEN mutation., Conclusion: BRRS should be considered in children with extreme macrocephaly as it is the most consistent clinical feature seen, particularly where there is a family history of macrocephaly.

Rubinstein-Taybi syndrome (RSTS) is a heterogeneous disorder with approximately 45-55% of patients showing mutations in the CREB binding protein and a further 3% of patients having mutations in EP300. We report a male child with a deletion of exons 3-8 of the EP300 gene who has RSTS. He has a milder skeletal phenotype, a finding that has been described in other cases with EP300 mutations. The mother suffered from pre-eclampsia and HELLP syndrome in the pregnancy. She subsequently developed a mullerian tumor of her cervix 6 years after the birth of her son.

The aim of this study was to ascertain the diagnostic yield following a routine genetics clinic referral for the assessment of global developmental delay. Detailed retrospective review of 119 complete consecutive case notes of patients referred to one single clinical geneticist over a 14 month time period was undertaken (n = 119; 54 males, 65 females). The age at initial review ranged from 2 months to 37 years 3 months (mean 8 y 3 mo [SD 7 y 10 mo]). We made a diagnosis in 36/119 (30%); 21/36 were new diagnoses and 15/36 were confirmations of diagnoses. We removed a wrong diagnostic label in 8/119 (7%). In 3/8 we were able to achieve a diagnosis but in 5/8 no alternative diagnosis was reached. We had a better diagnostic rate where the patients were dysmorphic (odds ratio [OR] 1.825; 95% confidence interval [CI] 1.065 to 3.128, p = 0.044). In the majority, the diagnosis was made by clinical examination only. Molecular diagnosis was reached in seven cases. Five cases were confirmed by cytogenetic analysis. Brain magnetic resonance imaging (MRI) revealed a diagnosis in three cases. This study confirms the importance of a clinical genetics assessment in the investigation of global developmental delay.

Synthetic riboswitches constructed from RNA aptamers provide a means to control bacterial gene expression using exogenous ligands. A common theme among riboswitches that function at the translational level is that the RNA aptamer interacts with the ribosome-binding site (RBS) of a gene via an intervening sequence known as an expression platform. Structural rearrangements of the expression platform convert ligand binding into a change in gene expression. While methods for selecting RNA aptamers that bind ligands are well established, few general methods have been reported for converting these aptamers into synthetic riboswitches with desirable properties. We have developed two such methods that not only provide the throughput of genetic selections, but also feature the quantitative nature of genetic screens. One method, based on cell motility, is operationally simple and requires only standard consumables; while the other, based on fluorescence-activated cell sorting (FACS), is particularly adept at identifying synthetic riboswitches that are highly dynamic and display very low levels of background expression in the absence of the ligand. Here we present detailed procedures for screening libraries for riboswitches using the two methods.

Mucopolysaccharidosis type 1 (MPS1) is an autosomal recessive disorder with severe, moderate and mild phenotypes: Hurler, Hurler-Scheie and Scheie syndromes. We estimated incidence (2001-2006) and prevalence (2002 census) of MPS1 in the Irish Republic (ROI) using population data, database and chart review of all live MPS1 patients attending two specialised centres. Patient genotypes, ethnicity, province of origin, age at diagnosis and presenting features were recorded. Thirty-one patients (14 females, 17 males) were alive, 27 of whom were <15 years. Twenty-six patients had Hurler syndrome, four had Hurler-Scheie and one had Scheie syndrome. The birth incidence was 1 in 26 206 births with a carrier frequency of 1 in 81. Of note, 19/26 (73%) Hurler patients were Irish Travellers. Amongst Irish Travellers the incidence was 1 in 371 with a carrier frequency of 1 in 10. This is the highest recorded incidence worldwide. Given the morbidity and mortality associated with delayed treatment we recommend targeted newborn screening for this population.

Riboswitches regulate gene expression through direct, small molecule-mRNA interactions. The creation of new synthetic riboswitches from in vitro selected aptamers benefits from rapid, high-throughput methods for identifying switches capable of triggering dramatic changes in gene expression in the presence of a desired ligand. Here we present a flow cytometry-based screen for identifying synthetic riboswitches that induce robust increases in gene expression in the presence of theophylline. The performance characteristics of our newly identified riboswitches exceed those of previously described natural and synthetic riboswitches. Sequencing data and structure probing experiments reveal the ribosome binding site to be an important determinant of how well a switch performs and may provide insights into the design of new synthetic riboswitches.

Context: Familial glucocorticoid deficiency (FGD) is an autosomal recessive disorder characterized by distinct clinical, biochemical, and genetic abnormalities. The prevalence of FGD is unknown, with the likelihood that cases remain undiagnosed. We noted a significant proportion of our FGD cases are Irish Travelers. Irish Travelers are an endogamous nomadic group ethnically and genetically distinct from Roma gypsies., Aims: The objective of the study was to describe the clinical features and assess the prevalence of FGD amongst Irish Travelers in the Republic of Ireland and describe their phenotype., Methods: Diagnosis of FGD was based on clinical features, high ACTH, and low cortisol concentrations with normal renin and aldosterone concentrations and exclusion of other causes of adrenal failure. Data from the Republic of Ireland Census 2006 were used., Results: We identified 21 cases of FGD, generating an overall prevalence of one in 201,898. We report nine Irish Travelers (five females) with FGD related to a new gene negative for melanocortin-2 receptor and melanocortin-2 receptor accessory protein mutations. Of a total population of 22,557 Travelers, this yields a disease prevalence of one in 2506 with a carrier frequency of one in 25 in this group and represents a prevalence of one in 665 and a carrier frequency of one in 13 in the 4- to 15-yr Traveler age group. All nine children had a later onset of FGD due to the fact that their initial investigations revealed normal cortisol (422-575 nmol/liter) and ACTH (<34 ng/liter) concentrations., Conclusion: We report a high prevalence of FGD among Irish Travelers. Their subtle phenotype and initial normal biochemistry may delay the early diagnosis of FGD.

This report describes the case of a child with Kabuki syndrome, hypoplastic left heart syndrome, and right-sided partial anomalous pulmonary venous drainage to the inferior vena cava. The child underwent successful Norwood and Glenn palliative procedures. At the age of 9 months, the genetic condition was recognized. This represents the first report describing this combination of findings for Kabuki syndrome.

Langer-Giedion syndrome results from a microdeletion at 8q24.1 encompassing the EXT1 and the adjacent TRPS1 gene. We report on a boy with an oligo array-cgh characterized small microdeletion involving EXT1 alone but with some features of Langer-Giedion syndrome suggesting a functional disturbance of TRPS1. This boy, in addition to a mild Langer-Giedion like phenotype, also had some unusual features including prominent toe pads and fat pads on the soles of his feet similar to those described in Pierpont syndrome., (2008 Wiley-Liss, Inc.)

Genetic counselling for families with BRCA1 & 2 has been available in Ireland since 1998. We describe the follow-on cascade from the initial 29 index cases that tested positive for either gene. 28 of the index cases were female and 1 was male. Their combined sibship and offspring totalled 125 and 129 respectively. Of the 125 siblings, 21/72 (29%) females and 10/53 (19%) males came forward for counselling and all were tested. Of the 129 at risk offspring, 56 (43%) [25 females and 31 males] were over 18 years and therefore were eligible for testing. 20/25 (80%) females and 6/31 (19%) males came for counselling and all bar one female was tested. In summary, 31/125 (25%) at risk siblings were tested and 25/56 (45%) offspring were tested. Only one person, a daughter of an affected individual who attended clinic, declined testing. The remaining 197 (77%) individuals have not come forward for counselling. Our results suggest that a) there is a low-moderate testing rate in Ireland when compared to other European centres; and that b) daughters of BRCA1/2 carriers are more likely to come forward for testing than female siblings. Specific factors which appeared to influence attendance included poor dissemination of information among families about the test; and lower levels of communication among siblings than within the nuclear family.

Many genetic diseases have been linked to the dysfunction of primary cilia, which occur nearly ubiquitously in the body and act as solitary cellular mechanosensory organelles. The list of clinical manifestations and affected tissues in cilia-related disorders (ciliopathies) such as nephronophthisis is broad and has been attributed to the wide expression pattern of ciliary proteins. However, little is known about the molecular mechanisms leading to this dramatic diversity of phenotypes. We recently reported hypomorphic NPHP3 mutations in children and young adults with isolated nephronophthisis and associated hepatic fibrosis or tapetoretinal degeneration. Here, we chose a combinatorial approach in mice and humans to define the phenotypic spectrum of NPHP3/Nphp3 mutations and the role of the nephrocystin-3 protein. We demonstrate that the pcy mutation generates a hypomorphic Nphp3 allele that is responsible for the cystic kidney disease phenotype, whereas complete loss of Nphp3 function results in situs inversus, congenital heart defects, and embryonic lethality in mice. In humans, we show that NPHP3 mutations can cause a broad clinical spectrum of early embryonic patterning defects comprising situs inversus, polydactyly, central nervous system malformations, structural heart defects, preauricular fistulas, and a wide range of congenital anomalies of the kidney and urinary tract (CAKUT). On the functional level, we show that nephrocystin-3 directly interacts with inversin and can inhibit like inversin canonical Wnt signaling, whereas nephrocystin-3 deficiency leads in Xenopus laevis to typical planar cell polarity defects, suggesting a role in the control of canonical and noncanonical (planar cell polarity) Wnt signaling.

The 8p23.1 deletion syndrome is established but not an equivalent duplication syndrome. Here, we report five patients; a de novo prenatal case and two families in which 8p23.1 duplications have been directly transmitted from mothers to children. Dual-colour fluorescent in situ hybridisation, multiplex ligation-dependent probe amplification analysis and customised oligonucleotide array comparative genomic hybridisation (oaCGH) indicated an approximately 3.75 Mb duplication of most of band 8p23.1 between the olfactory receptor/defensin repeats (ORDRs) in all cases. However, oaCGH revealed an additional duplication of 500 kb adjacent to the proximal ORDR in Family 1 and an additional deletion of 3.14 Mb within the Nablus Mask-Like Facial Syndrome region of 8q22.1 in Family 2. Copy number variation at introns 4-5 of the GATA4 gene was also identified. This 8p23.1 duplication syndrome is associated with a characteristic facial phenotype including a prominent forehead and arched eyebrows. Adrenal insufficiency, Tetralogy of Fallot, partial 2/3 syndactyly of the toes and cleft palate in some individuals may be explained by ascertainment bias, incomplete penetrance and/or the presence of the microdeletion in Family 2. The duplication is compatible with normal early childhood development but, although our adult cases live independent lives with varying degrees of support, learning difficulties have been experienced by some family members. We conclude that the 8p23.1 duplication syndrome is a genomic condition with an emerging but variable phenotype that may be under-diagnosed. Our results demonstrate that direct transmission does not distinguish genuine duplications from euchromatic variants and illustrate the power of array CGH to reveal unexpected additional imbalances in affected patients.

Background: The feasibility and value of transthoracic dobutamine stress echocardiography (DSE) in patients scheduled for bariatric surgery has not been investigated., Methods: We evaluated 611 patients (86.6% female, 42 +/- 10 years, 136 +/- 18 kg, BMI 48.0 +/- 6.1 kg/m2) referred for DSE prior to surgery between February 2000 and July 2005. Mortality and major cardiovascular events (cardiac death, acute coronary syndrome, and urgent revascularization) were recorded 30-days postoperatively and at 6 months., Results: Adequate baseline imaging quality was achieved in 590 patients (96.6%), with use of echocardiographic contrast agents in 426 patients (72.2%); the remaining 21 patients (3.4%) were referred for alternative preoperative testing. There were no serious adverse events during DSE, which was negative in 545 patients (92.4%). The test was inconclusive in 38 patients (6.4%), requiring alternative investigations, and positive in 7 patients (1.2%). Eventually, 595 patients proceeded to surgery: 539 with DSE-based risk stratification and 56 with risk stratification based on alternative testing. Laparoscopic procedures were employed in 77.0% of patients. There were 3 perioperative deaths, all attributed to sepsis (perioperative mortality 0.50%), but no major cardiovascular events at 30-days. One patient (evaluated prior to surgery with alternative testing) experienced an acute coronary syndrome during the following 6 months (event rate 0.17%)., Conclusion: Transthoracic DSE is feasible and safe in morbidly obese patients undergoing bariatric surgery; implementation of echocardiographic contrast agents allows for adequate imaging quality in the majority of these patients. However, the very low risk of contemporary bariatric procedures questions the need for routine preoperative stress testing in asymptomatic patients.

Aicardi-Goutieres syndrome (AGS) is a genetic encephalopathy whose clinical features mimic those of acquired in utero viral infection. AGS exhibits locus heterogeneity, with mutations identified in genes encoding the 3'-->5' exonuclease TREX1 and the three subunits of the RNASEH2 endonuclease complex. To define the molecular spectrum of AGS, we performed mutation screening in patients, from 127 pedigrees, with a clinical diagnosis of the disease. Biallelic mutations in TREX1, RNASEH2A, RNASEH2B, and RNASEH2C were observed in 31, 3, 47, and 18 families, respectively. In five families, we identified an RNASEH2A or RNASEH2B mutation on one allele only. In one child, the disease occurred because of a de novo heterozygous TREX1 mutation. In 22 families, no mutations were found. Null mutations were common in TREX1, although a specific missense mutation was observed frequently in patients from northern Europe. Almost all mutations in RNASEH2A, RNASEH2B, and RNASEH2C were missense. We identified an RNASEH2C founder mutation in 13 Pakistani families. We also collected clinical data from 123 mutation-positive patients. Two clinical presentations could be delineated: an early-onset neonatal form, highly reminiscent of congenital infection seen particularly with TREX1 mutations, and a later-onset presentation, sometimes occurring after several months of normal development and occasionally associated with remarkably preserved neurological function, most frequently due to RNASEH2B mutations. Mortality was correlated with genotype; 34.3% of patients with TREX1, RNASEH2A, and RNASEH2C mutations versus 8.0% RNASEH2B mutation-positive patients were known to have died (P=.001). Our analysis defines the phenotypic spectrum of AGS and suggests a coherent mutation-screening strategy in this heterogeneous disorder. Additionally, our data indicate that at least one further AGS-causing gene remains to be identified.

A girl with aniridia, microphthalmia, microcephaly and café au lait macules was found to have mutations in PAX6, NF1 and OTX2. A novel PAX6 missense mutation (p.R38W) was inherited from her mother whose iris phenotype had not been evident because of ocular neurofibromatosis. Analysis of the NF1 gene in the proband, prompted by the mother's diagnosis and the presence of café au lait spots, revealed a nonsense mutation (p.R192X). Subsequently an OTX2 nonsense mutation (p.Y179X) was identified and shown to be inherited from her father who was initially diagnosed with Leber's congenital amaurosis. Since individual mutations in PAX6, OTX2 or NF1 can cause a variety of severe developmental defects, the proband's phenotype is surprisingly mild. This case shows that patients with complex phenotypes should not be eliminated from subsequent mutation analysis after one or even two mutations are found.

Bonamia ostreae is a protistan parasite of the European flat oyster, Ostrea edulis. Though direct transmission of the parasite can occur between oysters, it is unclear if this represents the complete life cycle of the parasite, and the role of a secondary or intermediate host or carrier species cannot be ruled out. In this preliminary study, benthic macroinvertebrates and zooplankton from a B. ostreae-endemic area were screened for the presence of parasite DNA, using polymerase chain reaction (PCR). Eight benthic macroinvertebrates and nineteen grouped zooplankton samples gave positive results. Certain species, found positive for the parasite DNA, were then used in laboratory transmission trials, to investigate if they could infect naïve oysters. Transmission of B. ostreae was effected to two naïve oysters cohabiting with the brittle star, Ophiothrix fragilis.

Obesity-related glucose intolerance is a function of hepatic (homeostatic model assessment-insulin resistance [HOMA-IR]) and peripheral insulin resistance (S(i)) and beta-cell dysfunction. We determined relationships between changes in these measures, visceral (VAT) and subcutaneous (SAT) adipose tissue, and systemic adipocytokine biomarkers 1 and 6 months after surgical weight loss. HOMA-IR decreased significantly (-50%) from baseline by 1 month and decreased further (-67%) by 6 months, and S(i) was improved by 6 months (2.3-fold) weight loss. Plasma concentrations of leptin decreased and adiponectin increased significantly by 1 month, and decreases in interleukin-6, C-reactive protein (CRP), and tumor necrosis factor-alpha were observed at 6 months of weight loss. Longitudinal decreases in CRP (r = -0.53, P < 0.05) were associated with increases in S(i), and decreases in HOMA-IR were related to increases in adiponectin (r = -0.37, P < 0.05). Decreases in VAT were more strongly related to increases in adiponectin and decreases in CRP than were changes in general adiposity or SAT. Thus, in severely obese women, specific loss of VAT leads to acute improvements in hepatic insulin sensitivity mediated by increases in adiponectin and in peripheral insulin sensitivity mediated by decreases in CRP.