21. |
|
|
22. |
- Casey, Jillian P, et al.
(författare)
-
A novel approach of homozygous haplotype sharing identifies candidate genes in autism spectrum disorder.
- 2012
-
Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 131:4, s. 565-579
-
Tidskriftsartikel (refereegranskat)abstract
- Autism spectrum disorder (ASD) is a highly heritable disorder of complex and heterogeneous aetiology. It is primarily characterized by altered cognitive ability including impaired language and communication skills and fundamental deficits in social reciprocity. Despite some notable successes in neuropsychiatric genetics, overall, the high heritability of ASD (~90%) remains poorly explained by common genetic risk variants. However, recent studies suggest that rare genomic variation, in particular copy number variation, may account for a significant proportion of the genetic basis of ASD. We present a large scale analysis to identify candidate genes which may contain low-frequency recessive variation contributing to ASD while taking into account the potential contribution of population differences to the genetic heterogeneity of ASD. Our strategy, homozygous haplotype (HH) mapping, aims to detect homozygous segments of identical haplotype structure that are shared at a higher frequency amongst ASD patients compared to parental controls. The analysis was performed on 1,402 Autism Genome Project trios genotyped for 1 million single nucleotide polymorphisms (SNPs). We identified 25 known and 1,218 novel ASD candidate genes in the discovery analysis including CADM2, ABHD14A, CHRFAM7A, GRIK2, GRM3, EPHA3, FGF10, KCND2, PDZK1, IMMP2L and FOXP2. Furthermore, 10 of the previously reported ASD genes and 300 of the novel candidates identified in the discovery analysis were replicated in an independent sample of 1,182 trios. Our results demonstrate that regions of HH are significantly enriched for previously reported ASD candidate genes and the observed association is independent of gene size (odds ratio 2.10). Our findings highlight the applicability of HH mapping in complex disorders such as ASD and offer an alternative approach to the analysis of genome-wide association data.
|
|
23. |
- Cavalli, Marco, et al.
(författare)
-
Allele-specific transcription factor binding to common and rare variants associated with disease and gene expression
- 2016
-
Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 135:5, s. 485-497
-
Tidskriftsartikel (refereegranskat)abstract
- Genome-wide association studies (GWAS) have identified a large number of disease-associated SNPs, but in few cases the functional variant and the gene it controls have been identified. To systematically identify candidate regulatory variants, we sequenced ENCODE cell lines and used public ChIP-seq data to look for transcription factors binding preferentially to one allele. We found 9962 candidate regulatory SNPs, of which 16 % were rare and showed evidence of larger functional effect than common ones. Functionally rare variants may explain divergent GWAS results between populations and are candidates for a partial explanation of the missing heritability. The majority of allele-specific variants (96 %) were specific to a cell type. Furthermore, by examining GWAS loci we found >400 allele-specific candidate SNPs, 141 of which were highly relevant in our cell types. Functionally validated SNPs support identification of an SNP in SYNGR1 which may expose to the risk of rheumatoid arthritis and primary biliary cirrhosis, as well as an SNP in the last intron of COG6 exposing to the risk of psoriasis. We propose that by repeating the ChIP-seq experiments of 20 selected transcription factors in three to ten people, the most common polymorphisms can be interrogated for allele-specific binding. Our strategy may help to remove the current bottleneck in functional annotation of the genome.
|
|
24. |
- Cavelier, Lucia, et al.
(författare)
-
MtDNA substitution rate and segregation of heteroplasmy in coding andnoncoding regions
- 2000
-
Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 107:1, s. 45-50
-
Tidskriftsartikel (refereegranskat)abstract
- The mitochondrial DNA (mtDNA) substitution rate and segregation of heteroplasmy were studied for the non-coding control region (D-loop) and 500 bp of the coding region between nucleotide positions 5550 and 6050, by sequence analysis of blood samples from 194 individuals, representing 33 maternal lineages. No homoplasmic nucleotide substitutions were detected in a total of 292 transmissions. The estimated substitution rate per nucleotide per million years for the control region (micro>0.21, 95% CI 0-0.6) was not significantly different from that for the coding region (micro>0.54, 95% CI 0-1.0). Variation in the length of homopolymeric C streches was observed at three sites in the control region (positions 65, 309 and 16,189), all of which were in the heteroplasmic state. Segregation of heteroplasmic genotypes between generations was observed in several maternal pedigrees. At position 309, a longer poly C tract length was strongly associated with a higher probability for heteroplasmy and rapid segregation between generations. The length heteroplasmy at positions 65 and 16,189 was found at low frequency and was confined to a few families.
|
|
25. |
|
|
26. |
- Dahl, N, et al.
(författare)
-
DNA linkage analysis of X-linked retinoschisis.
- 1988
-
Ingår i: Human Genetics. - 0340-6717 .- 1432-1203. ; 78:3, s. 228-32
-
Tidskriftsartikel (refereegranskat)abstract
- Four families with juvenile retionoschisis (RS) have been studied by linkage analysis utilizing eleven polymorphic X-chromosomal markers. The results suggest a close linkage between DXS43, DXS41, and DXS208 and the RS locus at Xp22. The RS locus is distal to the OTC locus, DXS84, and the DMD locus but proximal to DXS85. No recombination events were observed between the RS locus and DXS43 and DXS41. The maximum likelihood estimate of the recombination fraction (theta) was thus zero and the peak lod scores (z) were 4.98 (DXS43) and 4.09 (DXS41). The linkage data suggest that the gene order on Xp is DXS85-(DXS43, RS, DXS41)-DMD-DXS84-OTC.
|
|
27. |
|
|
28. |
|
|
29. |
- Depienne, Christel, et al.
(författare)
-
Genetic and phenotypic dissection of 1q43q44 microdeletion syndrome and neurodevelopmental phenotypes associated with mutations in ZBTB18 and HNRNPU
- 2017
-
Ingår i: Human Genetics. - : Springer. - 0340-6717 .- 1432-1203. ; 136:4, s. 463-479
-
Tidskriftsartikel (refereegranskat)abstract
- Subtelomeric 1q43q44 microdeletions cause a syndrome associating intellectual disability, microcephaly, seizures and anomalies of the corpus callosum. Despite several previous studies assessing genotype-phenotype correlations, the contribution of genes located in this region to the specific features of this syndrome remains uncertain. Among those, three genes, AKT3, HNRNPU and ZBTB18 are highly expressed in the brain and point mutations in these genes have been recently identified in children with neurodevelopmental phenotypes. In this study, we report the clinical and molecular data from 17 patients with 1q43q44 microdeletions, four with ZBTB18 mutations and seven with HNRNPU mutations, and review additional data from 37 previously published patients with 1q43q44 microdeletions. We compare clinical data of patients with 1q43q44 microdeletions with those of patients with point mutations in HNRNPU and ZBTB18 to assess the contribution of each gene as well as the possibility of epistasis between genes. Our study demonstrates that AKT3 haploinsufficiency is the main driver for microcephaly, whereas HNRNPU alteration mostly drives epilepsy and determines the degree of intellectual disability. ZBTB18 deletions or mutations are associated with variable corpus callosum anomalies with an incomplete penetrance. ZBTB18 may also contribute to microcephaly and HNRNPU to thin corpus callosum, but with a lower penetrance. Co-deletion of contiguous genes has additive effects. Our results confirm and refine the complex genotype-phenotype correlations existing in the 1qter microdeletion syndrome and define more precisely the neurodevelopmental phenotypes associated with genetic alterations of AKT3, ZBTB18 and HNRNPU in humans.
|
|
30. |
|
|