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Ciliopathies are clinically and genetically heterogeneous diseases. We studied three patients from two independent families presenting with features of Joubert syndrome: abnormal breathing pattern during infancy, developmental delay/intellectual disability, cerebellar ataxia, molar tooth sign on magnetic resonance imaging scans, and polydactyly. We identified biallelic loss‐of‐function (LOF) variants in CBY1, segregating with the clinical features of Joubert syndrome in the families. CBY1 localizes to the distal end of the mother centriole, contributing to the formation and function of cilia. In accordance with the clinical and mutational findings in the affected individuals, we demonstrated that depletion of Cby1 in zebrafish causes ciliopathy‐related phenotypes. Levels of CBY1 transcript were found reduced in the patients compared with controls, suggesting degradation of the mutated transcript through nonsense‐mediated messenger RNA decay. Accordingly, we could detect CBY1 protein in fibroblasts from controls, but not from patients by immunofluorescence. Furthermore, we observed reduced ability to ciliate, increased ciliary length, and reduced levels of the ciliary proteins AHI1 and ARL13B in patient fibroblasts. Our data show that CBY1 LOF‐variants cause a ciliopathy with features of Joubert syndrome.

Background Joubert syndrome (JBTS) is a genetically heterogeneous group of neurodevelopmental syndromes caused by primary cilia dysfunction. Usually the neurological presentation starts with abnormal neonatal breathing followed by muscular hypotonia, psychomotor delay, and cerebellar ataxia. Cerebral MRI shows mid- and hindbrain anomalies including the molar tooth sign. We report a male patient with atypical presentation of Joubert syndrome type 23, thus expanding the phenotype. Case presentation Clinical features were consistent with JBTS already from infancy, yet the syndrome was not suspected before cerebral MRI later in childhood showed the characteristic molar tooth sign and ectopic neurohypophysis. From age 11 years seizures developed and after few years became increasingly difficult to treat, also related to inadequate compliance to therapy. He died at 23 years of sudden unexpected death in epilepsy (SUDEP). The genetic diagnosis remained elusive for many years, despite extensive genetic testing. We reached the genetic diagnosis by performing whole genome sequencing of the family trio and analyzing the data with the combination of one analysis pipeline for single nucleotide variants (SNVs)/indels and one for structural variants (SVs). This lead to the identification of the most common variant detected in patients with JBTS23 (OMIM# 616490), rs534542684, in compound heterozygosity with a 8.3 kb deletion in KIAA0586, not previously reported. Conclusions We describe for the first time ectopic neurohypophysis and SUDEP in JBTS23, expanding the phenotype of this condition and raising the attention on the possible severity of the epilepsy in this disease. We also highlight the diagnostic power of WGS, which efficiently detects SNVs/indels and in addition allows the identification of SVs.

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Huntington disease (HD) is a fatal neurodegenerative disorder caused by a gain-of-function mutation in HTT. Suppression of mutant HTT has emerged as a leading therapeutic strategy for HD, with allele-selective approaches targeting HTT SNPs now in clinical trials. Haplotypes associated with the HD mutation (A1, A2, A3a) represent panels of allele-specific gene silencing targets for efficient treatment of individuals with HD of Northern European and indigenous South American ancestry. Here we extend comprehensive haplotype analysis of the HD mutation to key populations of Southern European, South Asian, Middle Eastern, and admixed African ancestry. In each of these populations, the HD mutation occurs predominantly on the A2 HTT haplotype. Analysis of HD haplotypes across all affected population groups enables rational selection of candidate target SNPs for development of allele-selective gene silencing therapeutics worldwide. Targeting SNPs on the A1 and A2 haplotypes in parallel is essential to achieve treatment of the most HD-affected subjects in populations where HD is most prevalent. Current allele-specific approaches will leave a majority of individuals with HD untreated in populations where the HD mutation occurs most frequently on the A2 haplotype. We further demonstrate preclinical development of potent and selective ASOs targeting SNPs on the A2 HTT haplotype, representing an allele-specific treatment strategy for these individuals. On the basis of comprehensive haplotype analysis, we show the maximum proportion of HD-affected subjects that may be treated with three or four allele targets in different populations worldwide, informing current allele-specific HTT silencing strategies.

Neurodegeneration is the progressive loss of function of neurons and an inescapable event in incurable diseases involving Huntington Disease (HD), Parkinson Disease (PD), and Alzheimer Disease (AD). These and other such diseases share similar pathogenic mechanisms including atypical protein assembly, oxidative pathway dysfunction, and apoptotic cellular death. Neuronal degeneration may be exhibited at different levels like neuronal circuitry aligning from molecular to systemic levels.

Aim The use of prophylactic antibiotics for laparoscopy of uncomplicated gynecologic conditions is controversial. The aim of this study was to assess whether prophylactic antibiotics is necessary to prevent early postoperative infections and febrile morbidity in elective laparoscopic surgery for benign gynecologic conditions. Material and Methods A total of 218 patients who underwent laparoscopy for uncomplicated gynecologic conditions were recruited into the study over a 1-year period. Following recruitment into the study, they were divided into two groups (ratio 1:1). Patients were divided into either group A (n = 115) the therapy arm or group B (n = 103) the placebo arm. Group A patients received oral azithromycin 1 g daily for 3 days (i.e. the day before, the day of and the day after the procedure) while group B received placebo therapy. Post-procedural febrile and infection morbidity was analyzed. Results Morbidity was absent in 91.3% of patients in both groups A and B. The primary outcome measure of postoperative fever was present in eight patients from each group. The secondary outcome measure of postoperative infection was present in one patient from the group that did not receive prophylaxis (group B), who had a surgical site infection. There were no patients with urinary tract infection or pelvic inflammatory disease during the study. Conclusion Antibiotics prophylaxis was not able to achieve statistically significant reduction in postoperative febrile or infective morbidity in laparoscopic gynecologic surgery for benign uncomplicated conditions.

Introduction: Stored human samples and the establishment of biobanks are increasing in the world. Along with this there are the questions of ethics that arise such as the correct method of obtaining informed consent for research on stored samples and the policies involved in collaborative research using collected samples. This study is an attempt to evaluate the researchers, academics and policy makers’ views on these ethical aspects. Methods: This was an anonymised study involving a Sri Lankan population of researchers, ethics committee members, and policy makers. A self administered questionnaire was utilised as the study instrument. The questionnaire captured four major areas of interest: demographic characteristics of respondents, their attitudes on informed consent policy, their opinion on rights of collaborating researchers, their attitudes on dealing with international differences in regulatory frameworks. Results: The study included 55 responders with 40/55 (73%) agreeing that donors should receive the option of giving informed consent for future research, with 31/55 (56%) considering multiple- type consent options most appropriate. Regarding the issue of shared samples in collaborative research majority agreed that source country ethics review committee approval was necessary 53/55 (96%). Conclusion: The study concludes that sample donors should be given the option of giving advance consent to unspecified future research provided that future research is approved by an ethics committee. In collaborative research, it is necessary to involve ethics committees from donor countries in the research approval process.

The provision of medical and health genetics and genomics in the developing world lags far behind the developed world. In this chapter we laid out the framework for examining the provision of genetics and genomics based on consensus documents, and thereafter identified and highlighted some examples of good practice from the developing world so as to create visibility to those initiatives and to encourage others to take on such initiatives in their own settings. The ultimate goal is to ensure that no one is left behind as the wave of genomic medicine sweeps across the world from West to East.

49,XXXXY is a rare sex chromosome polysomy with an incidence of 1 in 85 000 male births. It has a characteristic triad of mental retardation, skeletal malformation and hypogonadism. This is the first case report of a child with 49,XXXXY syndrome and renal agenesis. This child was referred for genetic testing at 14 years of age due to facial dysmorphism and hypergonadotropic hypogonadism. He had coarse facial features, cryptorchidism of the right testis, genu valgus deformities, and patent ductus arteriosus which are known associations of 49,XXXXY syndrome. He also had agenesis of the right kidney, hydronephrosis of the left kidney with hydroureter which is not a known association of 49,XXXXY syndrome. The patient was the offspring of a mother with gestational diabetes. There is a strong correlation between maternal diabetes and congenital anomalies, especially renal and cardiovascular anomalies. Additionally, it has been noted that gestational diabetes increases the incidence of chromosomal aneuploidies. The teratogenic effects of maternal diabetes during embryogenesis may be the causative factor for the final phenotype of 49,XXXXY syndrome and renal agenesis. Conflict of interest:None declared.

Stored human samples and the establishment of biobanks are increasing in the world. Along with this there are the questions of ethics that arise such as the correct method of obtaining informed consent for research on stored samples and the policies involved in collaborative research using collected samples. This study is an attempt to evaluate the researchers, academics and policy makers' views on these ethical aspects.This was an anonymised study involving a Sri Lankan population of researchers, ethics committee members, and policy makers. A self administered questionnaire was utilised as the study instrument. The questionnaire captured four major areas of interest: demographic characteristics of respondents, their attitudes on informed consent policy, their opinion on rights of collaborating researchers, their attitudes on dealing with international differences in regulatory frameworks.The study included 55 responders with 40/55 (73%) agreeing that donors should receive the option of giving informed consent for future research, with 31/55 (56%) considering multiple- type consent options most appropriate. Regarding the issue of shared samples in collaborative research majority agreed that source country ethics review committee approval was necessary 53/55 (96%).The study concludes that sample donors should be given the option of giving advance consent to unspecified future research provided that future research is approved by an ethics committee. In collaborative research, it is necessary to involve ethics committees from donor countries in the research approval process.

The use of prophylactic antibiotics for laparoscopy of uncomplicated gynecologic conditions is controversial. The aim of this study was to assess whether prophylactic antibiotics is necessary to prevent early postoperative infections and febrile morbidity in elective laparoscopic surgery for benign gynecologic conditions.A total of 218 patients who underwent laparoscopy for uncomplicated gynecologic conditions were recruited into the study over a 1-year period. Following recruitment into the study, they were divided into two groups (ratio 1:1). Patients were divided into either group A (n = 115) the therapy arm or group B (n = 103) the placebo arm. Group A patients received oral azithromycin 1 g daily for 3 days (i.e. the day before, the day of and the day after the procedure) while group B received placebo therapy. Post-procedural febrile and infection morbidity was analyzed.Morbidity was absent in 91.3% of patients in both groups A and B. The primary outcome measure of postoperative fever was present in eight patients from each group. The secondary outcome measure of postoperative infection was present in one patient from the group that did not receive prophylaxis (group B), who had a surgical site infection. There were no patients with urinary tract infection or pelvic inflammatory disease during the study.Antibiotics prophylaxis was not able to achieve statistically significant reduction in postoperative febrile or infective morbidity in laparoscopic gynecologic surgery for benign uncomplicated conditions.

Background Spinocerebellar ataxias (SCA) are a group of hereditary neurodegenerative disorders. Prevalence of SCA subtypes differ worldwide. Autosomal dominant ataxias are the commonest types of inherited ataxias seen in Sri Lanka. The aim of the study is to determine the genetic etiology of patients with autosomal dominant ataxia in Sri Lanka and to describe the clinical features of each genetic subtype. Methods Thirty four patients with autosomal dominant ataxia were recruited. For every patient the following was done: recording of clinical details and genotyping for SCA 1, 2, 3, 6, 7, 8, 12, and 17. Results Sixty one per cent of the subjects were identified as SCA1. One subject had SCA2, 12 remain unidentified. Mean age at onset was 34.8 ± 10years for SCA1 and 32.7 ± 9.8 for non SCA1. 76% of SCA1 patients and 50% of non SCA1 were using walking aids. Quantification of symptoms and signs were similar in the SCA1 and non SCA1 groups. Clinical depression was evidenced in 68.4% of SCA1 and 75% non SCA-1 patients. Mean CAG repeat length in SCA1 patients was 52.0 ± 3.8, with greater anticipation seen with paternal inheritance. Conclusion SCA1 was the predominant subtype and showed similar phenotype to previous reports. However, disease severity was higher and depression more prevalent in this population than previously described.

Introduction: Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder with an incidence of 1 in 6000 to 1 in 10,000 live births. It is characterized by degeneration of the anterior horn cells of the spinal cord, leading to progressive symmetrical proximal muscle weakness and atrophy. About 95-98% of patients have a homozygous deletion of exons 7 and 8 in the telomeric copy of the survival motor neuron 1 gene ( SMN1 ). Another 2-5% are compound heterozygotes for deletion of exons 7 and 8 of SMN1 and a point mutation in SMN1 gene. The clinical and genetic pattern of SMA has not previously been reported in Sri Lanka. Genetic testing for SMA was introduced in Sri Lanka in 2007 since when 39 patients clinically suspected of SMA were referred for testing. Of these, 7 (18%) had homozygous deletions in exons 7 and 8. We describe the clinical and genetic features of these 7 SMA patients.

Background Huntington disease was one of the first neurological hereditary diseases for which genetic testing was made possible as early as 1993. The study describes the clinical and genetic characteristics of patients with Huntington disease in Sri Lanka. Methods Data of 35 consecutive patients tested from 2007 to 2012 at the Human Genetics Unit, Faculty of Medicine, University of Colombo was analyzed retrospectively. Clinical data and genetic diagnostic results were reviewed. Statistical analysis was performed using descriptive statistics. Results Thirty patients had fully penetrant (FP) CAG repeat mutations and 5 had reduced penetrant (RP) CAG repeat mutations. In the FP group mean ages of onset and diagnosis were 37.5 and 40.4 years, while in the RP group it was 63.0 and 64.8 years respectively. The age of diagnosis ranged from 15 to 72 years, with 2 patients with Juvenile onset (60 years) Huntington disease. The symptoms at diagnosis were predominantly motor (32/35 -91%). Three patients had psychiatric and behavioral disorders. The age difference between onset and genetic diagnosis showed significant delay in females compared to males (p HTT gene showed significant inverse correlation (p 2 = 0.727). Conclusions The clinical and genetic features seen in patients with Huntington disease in the Sri Lankan study population were similar to that previously reported in literature.

Background Potocki–Lupski syndrome is a microduplication syndrome associated with duplication at 17p11.2. Features include facial dysmorphism, moderate to mild cognitive impairment and behavioural abnormalities including autism spectrum disorders. Case presentation We describe a patient from Sri Lanka that was referred for genetic assessment at 4 years of age due to subtle facial dysmorphism and expressive language impairment. She was diagnosed with Potocki–Lupski syndrome through multiplex ligation probe amplification. She carried two duplications; one in 17p11.2 consistent with Potocki–Lupski, and one in Xq including the region for X-linked intellectual disability. Conclusion Despite the absence of expected behavioural symptoms, many features of this patient are in accordance with Potocki–Lupski syndrome. This is the first diagnosed patient in Sri Lanka.