Medical Genetics Commons^™

Global Dna Methylation Differences Involving Germline Structural Variation Impact Gene Expression In Pediatric Brain Tumors, Fengju Chen, Yiqun Zhang, Wei Li, Fritz J Sedlazeck, Lanlan Shen, Chad J Creighton

Children’s Nutrition Research Center Staff Publications

The extent of genetic variation and its influence on gene expression across multiple tissue and cellular contexts is still being characterized, with germline Structural Variants (SVs) being historically understudied. DNA methylation also represents a component of normal germline variation across individuals. Here, we combine germline SVs (by short-read sequencing) with tumor DNA methylation across 1292 pediatric brain tumor patients. For thousands of methylation probes for CpG Islands (CGIs) or enhancers, rare and common SV breakpoints upstream or downstream associate with differential methylation in tumors spanning various histologic types, a significant subset involving genes with SV-associated differential expression. Cancer predisposition genes …

Genetic Associations With C-Peptide Levels Before Type 1 Diabetes Diagnosis In At-Risk Relatives, Taylor M Triolo, Hemang M Parikh, Mustafa Tosur, Lauric A Ferrat, Lu You, Peter A Gottlieb, Richard A Oram, Suna Onengut-Gumuscu, Jeffrey P Krischer, Stephen S Rich, Andrea K Steck, Maria J Redondo

Children’s Nutrition Research Center Staff Publications

Objective: We sought to determine whether the type 1 diabetes genetic risk score-2 (T1D-GRS2) and single nucleotide polymorphisms are associated with C-peptide preservation before type 1 diabetes diagnosis.

Methods: We conducted a retrospective analysis of 713 autoantibody-positive participants who developed type 1 diabetes in the TrialNet Pathway to Prevention Study who had T1DExomeChip data. We evaluated the relationships of 16 known single nucleotide polymorphisms and T1D-GRS2 with area under the curve (AUC) C-peptide levels during oral glucose tolerance tests conducted in the 9 months before diagnosis.

Results: Higher T1D-GRS2 was associated with lower C-peptide AUC in the 9 months before …

Parental Age Effects And Rett Syndrome, Xiaolan Fang, Lauren M Baggett, Raymond C Caylor, Alan K Percy, Jeffrey L Neul, Jane B Lane, Daniel G Glaze, Tim A Benke, Eric D Marsh, Kathleen J Motil, Judy O Barrish, Fran E Annese, Steven A Skinner

Children’s Nutrition Research Center Staff Publications

Rett syndrome (RTT) is a progressive neurodevelopmental disorder, and pathogenic Methyl-CpG-binding Protein 2 (MECP2) variants are identified in >95% of individuals with typical RTT. Most of RTT-causing variants in MECP2 are de novo and usually on the paternally inherited X chromosome. While paternal age has been reported to be associated with increased risk of genetic disorders, it is unknown whether parental age contributes to the risk of the development of RTT. Clinical data including parental age, RTT diagnostic status, and clinical severity are collected from 1226 participants with RTT and confirmed MECP2 variants. Statistical analyses are performed using Student t-test, …

Tracking The Evolution Of Esophageal Squamous Cell Carcinoma Under Dynamic Immune Selection By Multi-Omics Sequencing, Sijia Cui, Nicholas Mcgranahan, Jing Gao, Peng Chen, Wei Jiang, Lingrong Yang, Li Ma, Junfang Liao, Tian Xie, Congying Xie, Tariq Enver, Shixiu Wu

Children’s Nutrition Research Center Staff Publications

Intratumoral heterogeneity (ITH) has been linked to decreased efficacy of clinical treatments. However, although genomic ITH has been characterized in genetic, transcriptomic and epigenetic alterations are hallmarks of esophageal squamous cell carcinoma (ESCC), the extent to which these are heterogeneous in ESCC has not been explored in a unified framework. Further, the extent to which tumor-infiltrated T lymphocytes are directed against cancer cells, but how the immune infiltration acts as a selective force to shape the clonal evolution of ESCC is unclear. In this study, we perform multi-omic sequencing on 186 samples from 36 primary ESCC patients. Through multi-omics analyses, …

Sequencing Individual Genomes With Recurrent Genomic Disorder Deletions: An Approach To Characterize Genes For Autosomal Recessive Rare Disease Traits, Bo Yuan, Katharina V Schulze, Nurit Assia Batzir, Jefferson Sinson, Hongzheng Dai, Wenmiao Zhu, Francia Bocanegra, Chin-To Fong, Jimmy Holder, Joanne Nguyen, Christian P Schaaf, Yaping Yang, Weimin Bi, Christine Eng, Chad Shaw, James R Lupski, Pengfei Liu

Children’s Nutrition Research Center Staff Publications

Background: In medical genetics, discovery and characterization of disease trait contributory genes and alleles depends on genetic reasoning, study design, and patient ascertainment; we suggest a segmental haploid genetics approach to enhance gene discovery and molecular diagnostics.

Methods: We constructed a genome-wide map for nonallelic homologous recombination (NAHR)-mediated recurrent genomic deletions and used this map to estimate population frequencies of NAHR deletions based on large-scale population cohorts and region-specific studies. We calculated recessive disease carrier burden using high-quality pathogenic or likely pathogenic variants from ClinVar and gnomAD. We developed a NIRD (NAHR deletion Impact to Recessive Disease) score for recessive …

The Concurrence Of Dna Methylation And Demethylation Is Associated With Transcription Regulation, Jiejun Shi, Jianfeng Xu, Yiling Elaine Chen, Jason Sheng Li, Ya Cui, Lanlan Shen, Jingyi Jessica Li, Wei Li

Children’s Nutrition Research Center Staff Publications

The mammalian DNA methylome is formed by two antagonizing processes, methylation by DNA methyltransferases (DNMT) and demethylation by ten-eleven translocation (TET) dioxygenases. Although the dynamics of either methylation or demethylation have been intensively studied in the past decade, the direct effects of their interaction on gene expression remain elusive. Here, we quantify the concurrence of DNA methylation and demethylation by the percentage of unmethylated CpGs within a partially methylated read from bisulfite sequencing. After verifying 'methylation concurrence' by its strong association with the co-localization of DNMT and TET enzymes, we observe that methylation concurrence is strongly correlated with gene expression. …