@article {143, title = {Secondary findings and carrier test frequencies in a large multiethnic sample.}, journal = {Genome Med}, volume = {7}, year = {2015}, month = {2015}, pages = {54}, abstract = {

BACKGROUND: Besides its growing importance in clinical diagnostics and understanding the genetic basis of Mendelian and complex diseases, whole exome sequencing (WES) is a rich source of additional information of potential clinical utility for physicians, patients and their families. We analyzed the frequency and nature of single nucleotide variants (SNVs) considered secondary findings and recessive disease allele carrier status in the exomes of 8554 individuals from a large, randomly sampled cohort study and 2514 patients from a study of presumed Mendelian disease having undergone WES.

METHODS: We used the same sequencing platform and data processing pipeline to analyze all samples and characterized the distributions of reported pathogenic (ClinVar, Human Gene Mutation Database (HGMD)) and predicted deleterious variants in the pre-specified American College of Medical Genetics and Genomics (ACMG) secondary findings and recessive disease genes in different ethnic groups.

RESULTS: In the 56 ACMG secondary findings genes, the average number of predicted deleterious variants per individual was 0.74, and the mean number of ClinVar reported pathogenic variants was 0.06. We observed an average of 10 deleterious and 0.78 ClinVar reported pathogenic variants per individual in 1423 autosomal recessive disease genes. By repeatedly sampling pairs of exomes, 0.5~\% of the randomly generated couples were at 25~\% risk of having an affected offspring for an autosomal recessive disorder based on the ClinVar variants.

CONCLUSIONS: By investigating reported pathogenic and novel, predicted deleterious variants we estimated the lower and upper limits of the population fraction for which exome sequencing may reveal additional medically relevant information. We suggest that the observed wide range for the lower and upper limits of these frequency numbers will be gradually reduced due to improvement in classification databases and prediction algorithms.

}, issn = {1756-994X}, doi = {10.1186/s13073-015-0171-1}, author = {Gambin, Tomasz and Jhangiani, Shalini N and Below, Jennifer E and Campbell, Ian M and Wiszniewski, Wojciech and Muzny, Donna M and Staples, Jeffrey and Morrison, Alanna C and Bainbridge, Matthew N and Penney, Samantha and McGuire, Amy L and Gibbs, Richard A and Lupski, James R and Boerwinkle, Eric} } @article {169, title = {Somatic mosaicism: implications for disease and transmission genetics.}, journal = {Trends Genet}, volume = {31}, year = {2015}, month = {2015 Jul}, pages = {382-92}, abstract = {

Nearly all of the genetic material among cells within an organism is identical. However, single-nucleotide variants (SNVs), small insertions/deletions (indels), copy-number variants (CNVs), and other structural variants (SVs) continually accumulate as cells divide during development. This process results in an organism composed of countless cells, each with its own unique personal genome. Thus, every human is undoubtedly mosaic. Mosaic mutations can go unnoticed, underlie genetic disease or normal human variation, and may be transmitted to the next generation as constitutional variants. We review the influence of the developmental timing of mutations, the mechanisms by which they arise, methods for detecting mosaic variants, and the risk of passing these mutations on to the next generation.

}, keywords = {Animals, Genetic Diseases, Inborn, Genome, Human, Humans, Mosaicism, Mutagenesis, Insertional, Mutation, Polymorphism, Single Nucleotide, Risk, Trinucleotide Repeat Expansion}, issn = {0168-9525}, doi = {10.1016/j.tig.2015.03.013}, author = {Campbell, Ian M and Shaw, Chad A and Stankiewicz, Pawel and Lupski, James R} }