ABSTRACT
X-linked intellectual disability (XLID) is a clinically and genetically heterogeneous disorder. During the past two decades in excess of 100 X-chromosome ID genes have been identified. Yet, a large number of families mapping to the X-chromosome remained unresolved suggesting that more XLID genes or loci are yet to be identified. Here, we have investigated 405 unresolved families with XLID. We employed massively parallel sequencing of all X-chromosome exons in the index males. The majority of these males were previously tested negative for copy number variations and for mutations in a subset of known XLID genes by Sanger sequencing. In total, 745 X-chromosomal genes were screened. After stringent filtering, a total of 1297 non-recurrent exonic variants remained for prioritization. Co-segregation analysis of potential clinically relevant changes revealed that 80 families (20%) carried pathogenic variants in established XLID genes. In 19 families, we detected likely causative protein truncating and missense variants in 7 novel and validated XLID genes (CLCN4, CNKSR2, FRMPD4, KLHL15, LAS1L, RLIM and USP27X) and potentially deleterious variants in 2 novel candidate XLID genes (CDK16 and TAF1). We show that the CLCN4 and CNKSR2 variants impair protein functions as indicated by electrophysiological studies and altered differentiation of cultured primary neurons from Clcn4(-/-) mice or after mRNA knock-down. The newly identified and candidate XLID proteins belong to pathways and networks with established roles in cognitive function and intellectual disability in particular. We suggest that systematic sequencing of all X-chromosomal genes in a cohort of patients with genetic evidence for X-chromosome locus involvement may resolve up to 58% of Fragile X-negative cases.
Subject(s)
Genetic Variation , Mental Retardation, X-Linked/genetics , Adaptor Proteins, Signal Transducing/genetics , Adolescent , Adult , Animals , Cells, Cultured , Chloride Channels/genetics , Chloride Channels/metabolism , Cohort Studies , Cyclin-Dependent Kinases/genetics , High-Throughput Nucleotide Sequencing , Histone Acetyltransferases/genetics , Humans , Intracellular Signaling Peptides and Proteins/genetics , Male , Mice, Knockout , Microfilament Proteins/genetics , Neurons/metabolism , Neurons/pathology , Nuclear Proteins/genetics , RNA, Messenger/metabolism , TATA-Binding Protein Associated Factors/genetics , Transcription Factor TFIID/genetics , Ubiquitin-Protein Ligases/geneticsABSTRACT
The immunoglobulin E (IgE)-associated locus on human chromosome 13q14 influencing asthma-related traits contains the genes PHF11 and SETDB2. SETDB2 is located in the same linkage disequilibrium region as PHF11 and polymorphisms within SETDB2 have been shown to associate with total serum IgE levels. In this report, we sequenced the 15 exons of SETDB2 and identified a single previously ungenotyped mutation (AT/G, rs386770867) in the 5'-untranslated region of the gene. The polymorphism was found to be significantly associated with serum IgE levels in our asthma cohort (P=0.0012). Electrophoretic mobility shift assays revealed that the transcription factor Ying Yang 1 binds to the AT allele, whereas SRY (Sex determining Region Y) binds to the G allele. Allele-specific transcription analysis (allelotyping) was performed in 35 individuals heterozygous for rs386770867 from a panel of 200 British families ascertained through probands with severe stage 3 asthma. The AT allele was found to be significantly overexpressed in these individuals (P=1.26×10(-21)). A dual-luciferase assay with the pGL3 luciferase reporter gene showed that the AT allele significantly affects transcriptional activities. Our results indicate that the IgE-associated AT/G polymorphism (rs386770867) regulates transcription of SETDB2.
Subject(s)
5' Untranslated Regions , Chromosomes, Human, Pair 13 , Histone-Lysine N-Methyltransferase/genetics , Immunoglobulin E/genetics , Protein Methyltransferases/genetics , Adolescent , Adult , Asthma/enzymology , Asthma/genetics , Child , Electrophoretic Mobility Shift Assay , Exons , Female , Humans , Immunoglobulin E/blood , Male , Middle Aged , Polymorphism, Single Nucleotide , White PeopleABSTRACT
OBJECTIVE: To compare the intelligence and grip strength of orthopaedic surgeons and anaesthetists. DESIGN: Multicentre prospective comparative study. SETTING: Three UK district general hospitals in 2011. PARTICIPANTS: 36 male orthopaedic surgeons and 40 male anaesthetists at consultant or specialist registrar grade. MAIN OUTCOME MEASURES: Intelligence test score and dominant hand grip strength. RESULTS: Orthopaedic surgeons had a statistically significantly greater mean grip strength (47.25 (SD 6.95) kg) than anaesthetists (43.83 (7.57) kg). The mean intelligence test score of orthopaedic surgeons was also statistically significantly greater at 105.19 (10.85) compared with 98.38 (14.45) for anaesthetists. CONCLUSIONS: Male orthopaedic surgeons have greater intelligence and grip strength than their male anaesthetic colleagues, who should find new ways to make fun of their orthopaedic friends.
Subject(s)
Anesthesiology , Clinical Competence , Hand Strength , Orthopedics , Adult , Attitude of Health Personnel , Humans , Intelligence , Male , Middle Aged , Physicians , Prospective StudiesABSTRACT
Rgs2 (regulator of G-protein signalling 2) gene recently was reported as a quantitative trait gene for anxious behaviour in mice and male Rgs2 knockout mice have been shown to be more anxious than wildtype mice. Therefore we investigated four non-coding single nucleotide polymorphisms in a sample of 173 patients with panic disorder and 173 matched controls of German descent. At the genotype level all four SNPs were associated with panic disorder (p = 0.02-0.05). At the haplotype level the strongest association was observed for a haplotype containing SNP3 and SNP 4 (subgroup men and men with agoraphobia: p = 0.01 and 0.03). This points towards a functional polymorphism at the 3' end of the gene. Our results support the hypothesis that variations of the Rgs2 gene play a role also for the development of anxiety in humans.
