@article {922, title = {Using to drive the diagnosis and understand the mechanisms of rare human diseases.}, journal = {Development}, volume = {147}, year = {2020}, month = {2020 09 28}, abstract = {

Next-generation sequencing has greatly accelerated the discovery of rare human genetic diseases. Nearly 45\% of patients have variants associated with known diseases but the unsolved cases remain a conundrum. Moreover, causative mutations can be difficult to pinpoint because variants frequently map to genes with no previous disease associations and, often, only one or a few patients with variants in the same gene are identified. Model organisms, such as , can help to identify and characterize these new disease-causing genes. Importantly, allow quick and sophisticated genetic manipulations, permit functional testing of human variants, enable the characterization of pathogenic mechanisms and are amenable to drug tests. In this Spotlight, focusing on microcephaly as a case study, we highlight how studies of human genes in have aided our understanding of human genetic disorders, allowing the identification of new genes in well-established signaling pathways.

}, keywords = {Animals, Disease Models, Animal, Drosophila melanogaster, Genetic Techniques, Human Genetics, Humans, Microcephaly, Rare Diseases}, issn = {1477-9129}, doi = {10.1242/dev.191411}, author = {Link, Nichole and Bellen, Hugo J} } @article {768, title = {The utility of exome sequencing for fetal pleural effusions.}, journal = {Prenat Diagn}, volume = {40}, year = {2020}, month = {2020 04}, pages = {590-595}, abstract = {

OBJECTIVE: We sought to evaluate the performance of exome sequencing (ES) in determining an underlying genetic etiology for cases of fetal pleural effusions.

STUDY DESIGN: We examined a prospective cohort series of fetal pleural effusions visualized sonographically between 1 April 2016 and 31 August 2017. Fetal pleural effusions attributed to twin sharing, anemia, or structural anomalies were excluded, as were all cases with a genetic diagnosis established by karyotype or chromosomal microarray analysis. The remaining cases with pleural effusions of unclear etiology were offered ES. ES was performed by clinical sequencing and/or sequencing under the Baylor-Hopkins Center for Mendelian Genomics{\textquoteright} (BHCMG) research platform. All cases were evaluated for novel genes or phenotypic expansion of disease-causing genes.

RESULTS: ES was performed on six probands affected by pleural effusions. A pathogenic variant was identified in one case (16.7\%). Four additional cases had variants of uncertain significance (VUS) in candidate genes of pathological interest. Neither clinical nor candidate genes were evident in the final case.

CONCLUSION: ES should be considered in the evaluation of prenatally detected idiopathic pleural effusions when other diagnostic workup for a genetic etiology has failed.

}, issn = {1097-0223}, doi = {10.1002/pd.5650}, author = {Jelin, Angie C and Sobreira, Nara and Wohler, Elizabeth and Solomon, Benjamin and Sparks, Teresa and Sagaser, Katelynn G and Forster, Katherine R and Miller, Jena and Witmer, P Dane and Hamosh, Ada and Valle, David and Blakemore, Karin} } @article {653, title = {Unique bioinformatic approach and comprehensive reanalysis improve diagnostic yield of clinical exomes.}, journal = {Eur J Hum Genet}, year = {2019}, month = {2019 Apr 12}, abstract = {

Clinical exome sequencing (CES) is increasingly being utilized; however, a large proportion of patients remain undiagnosed, creating a need for a systematic approach to increase the diagnostic yield. We have reanalyzed CES data for a clinically heterogeneous cohort of 102 probands with likely Mendelian conditions, including 74 negative cases and 28 cases with candidate variants, but reanalysis requested by clinicians. Reanalysis was performed by an interdisciplinary team using a validated custom-built pipeline, "Variant Explorer Pipeline" (VExP). This reanalysis approach and results were compared with existing literature. Reanalysis of candidate variants from CES in 28 cases revealed 1 interpretation that needed to be reclassified. A confirmed or potential genetic diagnosis was identified in 24 of 75 CES-negative/reclassified cases (32.0\%), including variants in known disease-causing genes (n = 6) or candidate genes (n = 18). This yield was higher compared with similar studies demonstrating the utility of this approach. In summary, reanalysis of negative CES in a research setting enhances diagnostic yield by about a third. This study suggests the need for comprehensive, continued reanalysis of exome data when molecular diagnosis is elusive.

}, issn = {1476-5438}, doi = {10.1038/s41431-019-0401-x}, author = {Schmitz-Abe, Klaus and Li, Qifei and Rosen, Samantha M and Nori, Neeharika and Madden, Jill A and Genetti, Casie A and Wojcik, Monica H and Ponnaluri, Sadhana and Gubbels, Cynthia S and Picker, Jonathan D and O{\textquoteright}Donnell-Luria, Anne H and Yu, Timothy W and Bodamer, Olaf and Brownstein, Catherine A and Beggs, Alan H and Agrawal, Pankaj B} } @article {380, title = {Unraveling genetic predisposition to familial or early onset gastric cancer using germline whole-exome sequencing.}, journal = {Eur J Hum Genet}, volume = {25}, year = {2017}, month = {2017 11}, pages = {1246-1252}, abstract = {

Recognition of individuals with a genetic predisposition to gastric cancer (GC) enables preventive measures. However, the underlying cause of genetic susceptibility to gastric cancer remains largely unexplained. We performed germline whole-exome sequencing on leukocyte DNA of 54 patients from 53 families with genetically unexplained diffuse-type and intestinal-type GC to identify novel GC-predisposing candidate genes. As young age at diagnosis and familial clustering are hallmarks of genetic tumor susceptibility, we selected patients that were diagnosed below the age of 35, patients from families with two cases of GC at or below age 60 and patients from families with three GC cases at or below age 70. All included individuals were tested negative for germline CDH1 mutations before or during the study. Variants that were possibly deleterious according to in silico predictions were filtered using several independent approaches that were based on gene function and gene mutation burden in controls. Despite a rigorous search, no obvious candidate GC predisposition genes were identified. This negative result stresses the importance of future research studies in large, homogeneous cohorts.

}, keywords = {Adult, Aged, Antigens, CD, Cadherins, Early Detection of Cancer, Exome, Female, Genetic Predisposition to Disease, Genetic Testing, Germ-Line Mutation, Humans, Male, Middle Aged, Sequence Analysis, DNA, Stomach Neoplasms}, issn = {1476-5438}, doi = {10.1038/ejhg.2017.138}, author = {Vogelaar, Ingrid P and van der Post, Rachel S and van Krieken, J Han Jm and Spruijt, Liesbeth and van Zelst-Stams, Wendy Ag and Kets, C Marleen and Lubinski, Jan and Jakubowska, Anna and Teodorczyk, Urszula and Aalfs, Cora M and van Hest, Liselotte P and Pinheiro, Hugo and Oliveira, Carla and Jhangiani, Shalini N and Muzny, Donna M and Gibbs, Richard A and Lupski, James R and de Ligt, Joep and Vissers, Lisenka E L M and Hoischen, Alexander and Gilissen, Christian and van de Vorst, Maartje and Goeman, Jelle J and Schackert, Hans K and Ranzani, Guglielmina N and Molinaro, Valeria and G{\'o}mez Garc{\'\i}a, Encarna B and Hes, Frederik J and Holinski-Feder, Elke and Genuardi, Maurizio and Ausems, Margreet G E M and Sijmons, Rolf H and Wagner, Anja and van der Kolk, Lizet E and Bj{\o}rnevoll, Inga and H{\o}berg-Vetti, Hildegunn and van Kessel, Ad Geurts and Kuiper, Roland P and Ligtenberg, Marjolijn J L and Hoogerbrugge, Nicoline} } @article {540, title = {Use of Exome Sequencing for Infants in Intensive Care Units: Ascertainment of Severe Single-Gene Disorders and Effect on Medical Management.}, journal = {JAMA Pediatr}, volume = {171}, year = {2017}, month = {2017 12 04}, pages = {e173438}, abstract = {

Importance: While congenital malformations and genetic diseases are a leading cause of early infant death, to our knowledge, the contribution of single-gene disorders in this group is undetermined.

Objective: To determine the diagnostic yield and use of clinical exome sequencing in critically ill infants.

Design, Setting, and Participants: Clinical exome sequencing was performed for 278 unrelated infants within the first 100 days of life who were admitted to Texas Children{\textquoteright}s Hospital in Houston, Texas, during a 5-year period between December 2011 and January 2017. Exome sequencing types included proband exome, trio exome, and critical trio exome, a rapid genomic assay for seriously ill infants.

Main Outcomes and Measures: Indications for testing, diagnostic yield of clinical exome sequencing, turnaround time, molecular findings, patient age at diagnosis, and effect on medical management among a group of critically ill infants who were suspected to have genetic disorders.

Results: The mean (SEM) age for infants participating in the study was 28.5 (1.7) days; of these, the mean (SEM) age was 29.0 (2.2) days for infants undergoing proband exome sequencing, 31.5 (3.9) days for trio exome, and 22.7 (3.9) days for critical trio exome. Clinical indications for exome sequencing included a range of medical concerns. Overall, a molecular diagnosis was achieved in 102 infants (36.7\%) by clinical exome sequencing, with relatively low yield for cardiovascular abnormalities. The diagnosis affected medical management for 53 infants (52.0\%) and had a substantial effect on informed redirection of care, initiation of new subspecialist care, medication/dietary modifications, and furthering life-saving procedures in select patients. Critical trio exome sequencing revealed a molecular diagnosis in 32 of 63 infants (50.8\%) at a mean (SEM) of 33.1 (5.6) days of life with a mean (SEM) turnaround time of 13.0 (0.4) days. Clinical care was altered by the diagnosis in 23 of 32 patients (71.9\%). The diagnostic yield, patient age at diagnosis, and medical effect in the group that underwent critical trio exome sequencing were significantly different compared with the group who underwent regular exome testing. For deceased infants (n = 81), genetic disorders were molecularly diagnosed in 39 (48.1\%) by exome sequencing, with implications for recurrence risk counseling.

Conclusions and Relevance: Exome sequencing is a powerful tool for the diagnostic evaluation of critically ill infants with suspected monogenic disorders in the neonatal and pediatric intensive care units and its use has a notable effect on clinical decision making.

}, keywords = {Adult, Critical Care, Disease Management, Exome, Genetic Counseling, Genetic Diseases, Inborn, Humans, Infant, Infant Care, Infant, Newborn, Intensive Care Units, Pediatric, Length of Stay, Retrospective Studies, Texas, Whole Exome Sequencing}, issn = {2168-6211}, doi = {10.1001/jamapediatrics.2017.3438}, author = {Meng, Linyan and Pammi, Mohan and Saronwala, Anirudh and Magoulas, Pilar and Ghazi, Andrew Ray and Vetrini, Francesco and Zhang, Jing and He, Weimin and Dharmadhikari, Avinash V and Qu, Chunjing and Ward, Patricia and Braxton, Alicia and Narayanan, Swetha and Ge, Xiaoyan and Tokita, Mari J and Santiago-Sim, Teresa and Dai, Hongzheng and Chiang, Theodore and Smith, Hadley and Azamian, Mahshid S and Robak, Laurie and Bostwick, Bret L and Schaaf, Christian P and Potocki, Lorraine and Scaglia, Fernando and Bacino, Carlos A and Hanchard, Neil A and Wangler, Michael F and Scott, Daryl and Brown, Chester and Hu, Jianhong and Belmont, John W and Burrage, Lindsay C and Graham, Brett H and Sutton, Vernon Reid and Craigen, William J and Plon, Sharon E and Lupski, James R and Beaudet, Arthur L and Gibbs, Richard A and Muzny, Donna M and Miller, Marcus J and Wang, Xia and Leduc, Magalie S and Xiao, Rui and Liu, Pengfei and Shaw, Chad and Walkiewicz, Magdalena and Bi, Weimin and Xia, Fan and Lee, Brendan and Eng, Christine M and Yang, Yaping and Lalani, Seema R} } @article {531, title = {Update on the Toriello-Carey syndrome.}, journal = {Am J Med Genet A}, volume = {170}, year = {2016}, month = {2016 10}, pages = {2551-8}, abstract = {

Toriello and Carey described a provisionally-unique syndrome comprised of agenesis of the corpus callosum, Pierre Robin anomaly, and a characteristic facial phenotype. Because the condition affected siblings, this entity was postulated to be an autosomal recessive multiple anomaly syndrome. Several patients were subsequently reported, and over time, it became apparent that the Toriello-Carey syndrome was etiologically heterogeneous. Based on previous reports, it is estimated that at least 20\% of patients with a clinical diagnosis of Toriello-Carey syndrome have a chromosomal anomaly as the basis of the phenotype. However, no basis for the non-chromosomal cases has been found. This review summarizes the literature to date and provides speculation regarding the possible explanations for failing to find the cause of Toriello-Carey syndrome. {\textcopyright} 2016 Wiley Periodicals, Inc.

}, keywords = {Agenesis of Corpus Callosum, Chromosome Aberrations, Craniofacial Abnormalities, Female, Genetic Association Studies, Heart Defects, Congenital, Humans, Limb Deformities, Congenital, Male, Phenotype, Pierre Robin Syndrome, Urogenital Abnormalities}, issn = {1552-4833}, doi = {10.1002/ajmg.a.37735}, author = {Toriello, Helga V and Colley, Chelsey and Bamshad, Michael} } @article {53, title = {Using Whole Exome Sequencing to Identify Candidate Genes With Rare Variants In Nonsyndromic Cleft Lip and Palate.}, journal = {Genet Epidemiol}, volume = {40}, year = {2016}, month = {2016 07}, pages = {432-41}, abstract = {

Studies suggest that nonsyndromic cleft lip and palate (NSCLP) is polygenic with variable penetrance, presenting a challenge in identifying all causal genetic variants. Despite relatively high prevalence of NSCLP among Amerindian populations, no large whole exome sequencing (WES) studies have been completed in this population. Our goal was to identify candidate genes with rare genetic variants for NSCLP in a Honduran population using WES. WES was performed on two to four members of 27 multiplex Honduran families. Genetic variants with a minor allele frequency > 1\% in reference databases were removed. Heterozygous variants consistent with dominant disease with incomplete penetrance were ascertained, and variants with predicted functional consequence were prioritized for analysis. Pedigree-specific P-values were calculated as the probability of all affected members in the pedigree being carriers, given that at least one is a carrier. Preliminary results identified 3,727 heterozygous rare variants; 1,282 were predicted to be functionally consequential. Twenty-three genes had variants of interest in >=3 families, where some genes had different variants in each family, giving a total of 50 variants. Variant validation via Sanger sequencing of the families and unrelated unaffected controls excluded variants that were sequencing errors or common variants not in databases, leaving four genes with candidate variants in >=3 families. Of these, candidate variants in two genes consistently segregate with NSCLP as a dominant variant with incomplete penetrance: ACSS2 and PHYH. Rare variants found at the same gene in all affected individuals in several families are likely to be directly related to NSCLP.

}, keywords = {Acetate-CoA Ligase, Alleles, Cleft Lip, Cleft Palate, Female, Gene Frequency, Genotype, Heterozygote, Hexokinase, High-Throughput Nucleotide Sequencing, Humans, Male, Mixed Function Oxygenases, Pedigree, Penetrance, Sequence Analysis, DNA, von Willebrand Factor}, issn = {1098-2272}, doi = {10.1002/gepi.21972}, author = {Aylward, Alana and Cai, Yi and Lee, Andrew and Blue, Elizabeth and Rabinowitz, Daniel and Haddad, Joseph} } @article {320, title = {Utilizing graph theory to select the largest set of unrelated individuals for genetic analysis.}, journal = {Genet Epidemiol}, volume = {37}, year = {2013}, month = {2013 Feb}, pages = {136-41}, abstract = {

Many statistical analyses of genetic data rely on the assumption of independence among samples. Consequently, relatedness is either modeled in the analysis or samples are removed to "clean" the data of any pairwise relatedness above a tolerated threshold. Current methods do not maximize the number of unrelated individuals retained for further analysis, and this is a needless loss of resources. We report a novel application of graph theory that identifies the maximum set of unrelated samples in any dataset given a user-defined threshold of relatedness as well as all networks of related samples. We have implemented this method into an open source program called Pedigree Reconstruction and Identification of a Maximum Unrelated Set, PRIMUS. We show that PRIMUS outperforms the three existing methods, allowing researchers to retain up to 50\% more unrelated samples. A unique strength of PRIMUS is its ability to weight the maximum clique selection using additional criteria (e.g. affected status and data missingness). PRIMUS is a permanent solution to identifying the maximum number of unrelated samples for a genetic analysis.

}, keywords = {Algorithms, Genome-Wide Association Study, HapMap Project, Humans, Models, Theoretical}, issn = {1098-2272}, doi = {10.1002/gepi.21684}, author = {Staples, Jeffrey and Nickerson, Deborah A and Below, Jennifer E} } @article {316, title = {A unified method for detecting secondary trait associations with rare variants: application to sequence data.}, journal = {PLoS Genet}, volume = {8}, year = {2012}, month = {2012}, pages = {e1003075}, abstract = {

Next-generation sequencing has made possible the detection of rare variant (RV) associations with quantitative traits (QT). Due to high sequencing cost, many studies can only sequence a modest number of selected samples with extreme QT. Therefore association testing in individual studies can be underpowered. Besides the primary trait, many clinically important secondary traits are often measured. It is highly beneficial if multiple studies can be jointly analyzed for detecting associations with commonly measured traits. However, analyzing secondary traits in selected samples can be biased if sample ascertainment is not properly modeled. Some methods exist for analyzing secondary traits in selected samples, where some burden tests can be implemented. However p-values can only be evaluated analytically via asymptotic approximations, which may not be accurate. Additionally, potentially more powerful sequence kernel association tests, variable selection-based methods, and burden tests that require permutations cannot be incorporated. To overcome these limitations, we developed a unified method for analyzing secondary trait associations with RVs (STAR) in selected samples, incorporating all RV tests. Statistical significance can be evaluated either through permutations or analytically. STAR makes it possible to apply more powerful RV tests to analyze secondary trait associations. It also enables jointly analyzing multiple cohorts ascertained under different study designs, which greatly boosts power. The performance of STAR and commonly used RV association tests were comprehensively evaluated using simulation studies. STAR was also implemented to analyze a dataset from the SardiNIA project where samples with extreme low-density lipoprotein levels were sequenced. A significant association between LDLR and systolic blood pressure was identified, which is supported by pharmacogenetic studies. In summary, for sequencing studies, STAR is an important tool for detecting secondary-trait RV associations.

}, keywords = {Blood Pressure, Computer Simulation, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, High-Throughput Nucleotide Sequencing, Humans, Italy, Lipoproteins, LDL, Models, Genetic, Phenotype, Quantitative Trait Loci, Software}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1003075}, author = {Liu, Dajiang J and Leal, Suzanne M} }