@article {372, title = {Homozygous and hemizygous CNV detection from exome sequencing data in a Mendelian disease cohort.}, journal = {Nucleic Acids Res}, volume = {45}, year = {2017}, month = {2017 02 28}, pages = {1633-1648}, abstract = {

We developed an algorithm, HMZDelFinder, that uses whole exome sequencing (WES) data to identify rare and intragenic homozygous and hemizygous (HMZ) deletions that may represent complete loss-of-function of the indicated gene. HMZDelFinder was applied to 4866 samples in the Baylor-Hopkins Center for Mendelian Genomics (BHCMG) cohort and detected 773 HMZ deletion calls (567 homozygous or 206 hemizygous) with an estimated sensitivity of 86.5\% (82\% for single-exonic and 88\% for multi-exonic calls) and precision of 78\% (53\% single-exonic and 96\% for multi-exonic calls). Out of 773 HMZDelFinder-detected deletion calls, 82 were subjected to array comparative genomic hybridization (aCGH) and/or breakpoint PCR and 64 were confirmed. These include 18 single-exon deletions out of which 8 were exclusively detected by HMZDelFinder and not by any of seven other CNV detection tools examined. Further investigation of the 64 validated deletion calls revealed at least 15 pathogenic HMZ deletions. Of those, 7 accounted for 17-50\% of pathogenic CNVs in different disease cohorts where 7.1-11\% of the molecular diagnosis solved rate was attributed to CNVs. In summary, we present an algorithm to detect rare, intragenic, single-exon deletion CNVs using WES data; this tool can be useful for disease gene discovery efforts and clinical WES analyses.

}, keywords = {Algorithms, Alternative Splicing, Cohort Studies, Computational Biology, Consanguinity, Datasets as Topic, DNA Copy Number Variations, Exome, Genetic Diseases, Inborn, Hemizygote, High-Throughput Nucleotide Sequencing, Homozygote, Humans, Inheritance Patterns, Models, Genetic, Pedigree, Reproducibility of Results, Sequence Deletion, Workflow}, issn = {1362-4962}, doi = {10.1093/nar/gkw1237}, author = {Gambin, Tomasz and Akdemir, Zeynep C and Yuan, Bo and Gu, Shen and Chiang, Theodore and Carvalho, Claudia M B and Shaw, Chad and Jhangiani, Shalini and Boone, Philip M and Eldomery, Mohammad K and Karaca, Ender and Bayram, Yavuz and Stray-Pedersen, Asbj{\o}rg and Muzny, Donna and Charng, Wu-Lin and Bahrambeigi, Vahid and Belmont, John W and Boerwinkle, Eric and Beaudet, Arthur L and Gibbs, Richard A and Lupski, James R} } @article {91, title = {Hutterite-type cataract maps to chromosome 6p21.32-p21.31, cosegregates with a homozygous mutation in LEMD2, and is associated with sudden cardiac death.}, journal = {Mol Genet Genomic Med}, volume = {4}, year = {2016}, month = {2016 Jan}, pages = {77-94}, abstract = {

BACKGROUND: Juvenile-onset cataracts are known among the Hutterites of North America. Despite being identified over 30~years ago, this autosomal recessive condition has not been mapped, and the disease gene is unknown.

METHODS: We performed whole exome sequencing of three Hutterite-type cataract trios and follow-up genotyping and mapping in four extended kindreds.

RESULTS: Trio exomes enabled genome-wide autozygosity mapping, which localized the disease gene to a 9.5-Mb region on chromosome 6p. This region contained two candidate variants, LEMD2 c.T38G and MUC21 c.665delC. Extended pedigrees recruited for variant genotyping revealed multiple additional relatives with juvenile-onset cataract, as well as six deceased relatives with both cataracts and sudden cardiac death. The candidate variants were genotyped in 84 family members, including 17 with cataracts; only the variant in LEMD2 cosegregated with cataracts (LOD~=~9.62). SNP-based fine mapping within the 9.5~Mb linked region supported this finding by refining the cataract locus to a 0.5- to 2.9-Mb subregion (6p21.32-p21.31) containing LEMD2 but not MUC21. LEMD2 is expressed in mouse and human lenses and encodes a LEM domain-containing protein; the c.T38G missense mutation is predicted to mutate a highly conserved residue within this domain (p.Leu13Arg).

CONCLUSION: We performed a genetic and genomic study of Hutterite-type cataract and found evidence for an association of this phenotype with sudden cardiac death. Using combined genetic and genomic approaches, we mapped cataracts to a small portion of chromosome 6 and propose that they result from a homozygous missense mutation in LEMD2.

}, issn = {2324-9269}, doi = {10.1002/mgg3.181}, author = {Boone, Philip M and Yuan, Bo and Gu, Shen and Ma, Zhiwei and Gambin, Tomasz and Gonzaga-Jauregui, Claudia and Jain, Mahim and Murdock, Todd J and White, Janson J and Jhangiani, Shalini N and Walker, Kimberly and Wang, Qiaoyan and Muzny, Donna M and Gibbs, Richard A and Hejtmancik, J Fielding and Lupski, James R and Posey, Jennifer E and Lewis, Richard A} }