@article {915, title = {Low-level parental somatic mosaic SNVs in exomes from a large cohort of trios with diverse suspected Mendelian conditions.}, journal = {Genet Med}, volume = {22}, year = {2020}, month = {2020 11}, pages = {1768-1776}, abstract = {

PURPOSE: The goal of this study was to assess the scale of low-level parental mosaicism in exome sequencing (ES) databases.

METHODS: We analyzed approximately 2000 family trio ES data sets from the Baylor-Hopkins Center for Mendelian Genomics (BHCMG) and Baylor Genetics (BG). Among apparent de novo single-nucleotide variants identified in the affected probands, we selected rare unique variants with variant allele fraction (VAF) between 30\% and 70\% in the probands and lower than 10\% in one of the parents.

RESULTS: Of 102 candidate mosaic variants validated using amplicon-based next-generation sequencing, droplet digital polymerase chain reaction, or blocker displacement amplification, 27 (26.4\%) were confirmed to be low- (VAF between 1\% and 10\%) or very low (VAF <1\%) level mosaic. Detection precision in parental samples with two or more alternate reads was 63.6\% (BHCMG) and 43.6\% (BG). In nine investigated individuals, we observed variability of mosaic ratios among blood, saliva, fibroblast, buccal, hair, and urine samples.

CONCLUSION: Our computational pipeline enables robust discrimination between true and false positive candidate mosaic variants and efficient detection of low-level mosaicism in ES samples. We confirm that the presence of two or more alternate reads in the parental sample is a reliable predictor of low-level parental somatic mosaicism.

}, keywords = {Exome, High-Throughput Nucleotide Sequencing, Humans, Mosaicism, Parents, Whole Exome Sequencing}, issn = {1530-0366}, doi = {10.1038/s41436-020-0897-z}, author = {Gambin, Tomasz and Liu, Qian and Karolak, Justyna A and Grochowski, Christopher M and Xie, Nina G and Wu, Lucia R and Yan, Yan Helen and Cao, Ye and Coban Akdemir, Zeynep H and Wilson, Theresa A and Jhangiani, Shalini N and Chen, Ed and Eng, Christine M and Muzny, Donna and Posey, Jennifer E and Yang, Yaping and Zhang, David Y and Shaw, Chad and Liu, Pengfei and Lupski, James R and Stankiewicz, Pawe{\l}} } @article {576, title = {Complex Compound Inheritance of Lethal Lung Developmental Disorders Due to Disruption of the TBX-FGF Pathway.}, journal = {Am J Hum Genet}, volume = {104}, year = {2019}, month = {2019 02 07}, pages = {213-228}, abstract = {

Primary defects in lung branching morphogenesis, resulting in neonatal lethal pulmonary hypoplasias, are incompletely understood. To elucidate the pathogenetics of human lung development, we studied a unique collection of samples obtained from deceased individuals with clinically and histopathologically diagnosed interstitial neonatal lung disorders: acinar dysplasia (n = 14), congenital alveolar dysplasia (n = 2), and other lethal lung hypoplasias (n = 10). We identified rare heterozygous copy-number variant deletions or single-nucleotide variants (SNVs) involving TBX4 (n = 8 and n = 2, respectively) or FGF10 (n = 2 and n = 2, respectively) in 16/26 (61\%) individuals. In addition to TBX4, the overlapping \~{}2 Mb recurrent and nonrecurrent deletions at 17q23.1q23.2 identified in seven individuals with lung hypoplasia also remove a lung-specific enhancer region. Individuals with coding variants involving either TBX4 or FGF10 also harbored at least one non-coding SNV in the predicted lung-specific enhancer region, which was absent in 13 control individuals with the overlapping deletions but without any structural lung anomalies. The occurrence of rare coding variants involving TBX4 or FGF10 with the putative hypomorphic non-coding SNVs implies a complex compound inheritance of these pulmonary hypoplasias. Moreover, they support the importance of TBX4-FGF10-FGFR2 epithelial-mesenchymal signaling in human lung organogenesis and help to explain the histopathological continuum observed in these rare lethal developmental disorders of the lung.

}, keywords = {DNA Copy Number Variations, Female, Fibroblast Growth Factor 10, Gene Expression Regulation, Gestational Age, Humans, Infant, Newborn, Infant, Newborn, Diseases, Lung, Lung Diseases, Male, Maternal Inheritance, Organogenesis, Paternal Inheritance, Pedigree, Polymorphism, Single Nucleotide, Receptor, Fibroblast Growth Factor, Type 2, Signal Transduction, T-Box Domain Proteins}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2018.12.010}, author = {Karolak, Justyna A and Vincent, Marie and Deutsch, Gail and Gambin, Tomasz and Cogn{\'e}, Benjamin and Pichon, Olivier and Vetrini, Francesco and Mefford, Heather C and Dines, Jennifer N and Golden-Grant, Katie and Dipple, Katrina and Freed, Amanda S and Leppig, Kathleen A and Dishop, Megan and Mowat, David and Bennetts, Bruce and Gifford, Andrew J and Weber, Martin A and Lee, Anna F and Boerkoel, Cornelius F and Bartell, Tina M and Ward-Melver, Catherine and Besnard, Thomas and Petit, Florence and Bache, Iben and T{\"u}mer, Zeynep and Denis-Musquer, Marie and Joubert, Madeleine and Martinovic, Jelena and B{\'e}n{\'e}teau, Claire and Molin, Arnaud and Carles, Dominique and Andr{\'e}, Gwenaelle and Bieth, Eric and Chassaing, Nicolas and Devisme, Louise and Chalabreysse, Lara and Pasquier, Laurent and Secq, V{\'e}ronique and Don, Massimiliano and Orsaria, Maria and Missirian, Chantal and Mortreux, J{\'e}r{\'e}mie and Sanlaville, Damien and Pons, Linda and K{\"u}ry, S{\'e}bastien and B{\'e}zieau, St{\'e}phane and Liet, Jean-Michel and Joram, Nicolas and Bihou{\'e}e, Tiphaine and Scott, Daryl A and Brown, Chester W and Scaglia, Fernando and Tsai, Anne Chun-Hui and Grange, Dorothy K and Phillips, John A and Pfotenhauer, Jean P and Jhangiani, Shalini N and Gonzaga-Jauregui, Claudia G and Chung, Wendy K and Schauer, Galen M and Lipson, Mark H and Mercer, Catherine L and van Haeringen, Arie and Liu, Qian and Popek, Edwina and Coban Akdemir, Zeynep H and Lupski, James R and Szafranski, Przemyslaw and Isidor, Bertrand and Le Caignec, Cedric and Stankiewicz, Pawe{\l}} } @article {430, title = {Variants in SKP1, PROB1, and IL17B genes at keratoconus 5q31.1-q35.3 susceptibility locus identified by whole-exome sequencing.}, journal = {Eur J Hum Genet}, volume = {25}, year = {2016}, month = {2016 01}, pages = {73-78}, abstract = {

Keratoconus (KTCN) is a protrusion and thinning of the cornea, resulting in impairment of visual function. The extreme genetic heterogeneity makes it difficult to discover factors unambiguously influencing the KTCN phenotype. In this study, we used whole-exome sequencing (WES) and Sanger sequencing to reduce the number of candidate genes at the 5q31.1-q35.3 locus and to prioritize other potentially relevant variants in an Ecuadorian family with KTCN. We applied WES in two affected KTCN individuals from the Ecuadorian family that showed a suggestive linkage between the KTCN phenotype and the 5q31.1-q35.3 locus. Putative variants identified by WES were further evaluated in this family using Sanger sequencing. Exome capture discovered a total of 173 rare (minor allele frequency <0.001 in control population) nonsynonymous variants in both affected individuals. Among them, 16 SNVs were selected for further evaluation. Segregation analysis revealed that variants c.475T>G in SKP1, c.671G>A in PROB1, and c.527G>A in IL17B in the 5q31.1-q35.3 linkage region, and c.850G>A in HKDC1 in the 10q22 locus completely segregated with the phenotype in the studied KTCN family. We demonstrate that a combination of various techniques significantly narrowed the studied genomic region and reduced the list of the putative exonic variants. Moreover, since this locus overlapped two other chromosomal regions previously recognized in distinct KTCN studies, our findings suggest that this 5q31.1-q35.3 locus might be linked with KTCN.

}, keywords = {Chromosomes, Human, Pair 5, Exome, Female, Gene Frequency, Genetic Linkage, Genetic Predisposition to Disease, Genome, Human, Hexokinase, High-Throughput Nucleotide Sequencing, Humans, Interleukin-17, Keratoconus, Male, Pedigree, Phenotype, Proteins, S-Phase Kinase-Associated Proteins}, issn = {1476-5438}, doi = {10.1038/ejhg.2016.130}, author = {Karolak, Justyna A and Gambin, Tomasz and Pitarque, Jose A and Molinari, Andrea and Jhangiani, Shalini and Stankiewicz, Pawel and Lupski, James R and Gajecka, Marzena} }