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Feingold, E.

Publications and source records attributed to Feingold, E..

9 recordsLinked to original sources

Optimizing Cognitive Phenotyping for Genetic Discovery in Alzheimer's Disease: A Simulation-Based Evaluation of Mini-Mental State Examination-Based Decline Measures

Background: Alzheimer's disease (AD) is a progressive neurodegenerative brain disorder characterized by cognitive decline. The Mini-Mental State Examination (MMSE) is a well-established screening tool that evaluates five cognitive domains with a total maximum score of 30. Although previous studies have suggested a genetic basis for cognitive decline in AD, inconsistent findings have been reported and may stem from variability in phenotypic definitions. Methods: We conducted a simulation study using parameters informed by real-world AD cohorts to model 10-year trajectories of MMSE scores in a sample of 500 individuals. Three types of cognitive decline patterns, including linear, quadratic, and sigmoid, were simulated. We incorporated realistic missing data mechanisms to reflect typical challenges in longitudinal data collection. From the simulated MMSE data, we derived seven distinct phenotypic measures of cognitive decline. Using statistical models that assumed additive genetic effects, we compared the power of these phenotypes across different missing data scenarios to identify the most effective strategies for phenotyping in genetic association studies. Results: Adjusting for baseline MMSE improved the statistical power of measures that do not incorporate it in the definition. Across all simulated scenarios, simpler non-repeated measures, such as "Slope", "dMMSEdt", and "Time-to-MMSE10", consistently outperformed the others. Conclusions: The phenotypic measures "Slope" and "dMMSE/dt" consistently showed strong performance across a range of data distributions, while "Time-to-MMSE10" was particularly effective in cohorts with a higher proportion of individuals experiencing severe cognitive decline. These findings highlight the importance of tailoring the choice of cognitive decline measures to the specific characteristics of the dataset, such as the severity and distribution of decline, to improve the power to detect genetic factors associated with Alzheimer's disease.

bioinformatics↗

Impact of low-frequency coding variants on human facial shape

The contribution of low-frequency variants to the genetic architecture of normal-range facial traits is unknown. We studied the influence of low-frequency coding variants (MAF < 1%) on multi-dimensional facial shape phenotypes in 2329 healthy Europeans. We used MultiSKAT o scan the exome for face-associated low-frequency variants in a gene-based manner. Seven genes (AR, CARS2, FTSJ1, HFE, LTB4R, TELO2, NECTIN1) were significantly associated with shape variation of the cheek, chin, nose and mouth areas. These genes displayed a wide range of phenotypic effects, with some impacting the full face and others affecting localized regions. The missense variant rs142863092 in NECTIN1 had a significant effect on chin morphology, and was predicted bioinformatically to be deleterious. NECTIN1 is an established craniofacial gene that underlies a human syndrome that includes a mandibular phenotype. We further showed that nectin1a mutations can affect zebrafish craniofacial development, with the size and shape of the mandibular cartilage altered in mutant animals. These Findings highlighted the role of low-frequency coding variants in normal-range facial variation.

genetics↗

Insights into the genetic architecture of the human face

The human face is complex and multipartite, and characterization of its genetic architecture remains intriguingly challenging. Applying GWAS to multivariate shape phenotypes, we identified 203 genomic regions associated with normal-range facial variation, 117 of which are novel. The associated regions are enriched for both genes relevant to craniofacial and limb morphogenesis and enhancer activity in cranial neural crest cells and craniofacial tissues. Genetic variants grouped by their contribution to similar aspects of facial variation show high within-group correlation of enhancer activity, and four SNP pairs display evidence of epistasis, indicating potentially coordinated actions of variants within the same cell types or tissues. In sum, our analyses provide new insights for understanding how complex morphological traits are shaped by both individual and coordinated genetic actions.

genetics↗

Coding de novo mutations identified by WGS reveal novel orofacial cleft genes

While de novo mutations (DNMs) are known to increase risk of congenital defects, DNMs have not been fully explored regarding orofacial clefts (OFCs), one of the most common human birth defects. Therefore, whole-genome sequencing of 756 case-parent trios of European, Colombian, and Taiwanese ancestry was performed to determine the contributions of coding DNMs to OFC risk. Overall, we identified a significant excess of loss-of-function DNMs in genes highly expressed in craniofacial tissues, as well as genes associated with known autosomal dominant OFC syndromes. This analysis also revealed roles for zinc-finger homeobox domain and SOX2-interacting genes in OFC etiology.

genetics↗

Whole genome sequencing of orofacial cleft trios from the Gabriella Miller Kids First Pediatric Research Consortium identifies a new locus on chromosome 21

Orofacial clefts (OFCs) are one of the most common birth defects worldwide and create a significant health burden. The majority of OFCs are non-syndromic, and the genetic component has been only partially determined. Here, we analyze whole genome sequence (WGS) data for association with risk of OFCs in European and Colombian families selected from a multicenter family-based OFC study. Part of the Gabriella Miller Kids First Pediatric Research Program, this is the first large-scale WGS study of OFC in parent-offspring trios. WGS provides deeper and more specific genetic data than currently available using imputation on single nucleotide polymorphic (SNP) marker panels. Here, association analysis of genome-wide single nucleotide variants (SNV) and short insertions and deletions (indels) identified a new locus on chromosome 21 in Colombian families, within a region known to be expressed during craniofacial development. This study reinforces the ancestry differences seen in the genetic etiology of OFCs, and the need for larger samples when for studying OFCs and other birth defects in admixed populations.

genetics↗

Novel genetic loci affecting facial shape variation in humans

The human face represents a combined set of highly heritable phenotypes, but knowledge on its genetic architecture remains limited despite the relevance for various fields of science and application. A series of genome-wide association studies on 78 facial shape phenotypes quantified from 3-dimensional facial images of 10,115 Europeans identified 24 genetic loci reaching genome-wide significant association, among which 17 were previously unreported. A multi-ethnic study in additional 7,917 individuals confirmed 13 loci including 8 unreported ones. A global map of polygenic face scores assembled facial features in major continental groups consistent with anthropological knowledge. Analyses of epigenomic datasets from cranial neural crest cells revealed abundant cis-regulatory activities at the face-associated genetic loci. Luciferase reporter assays in neural crest progenitor cells highlighted enhancer activities of several face-associated DNA variants. These results substantially advance our understanding of the genetic basis underlying human facial variation and provide candidates for future in-vivo functional studies.

genomics↗

A novel method for systematic genetic analysis and visualization of phenotypic heterogeneity applied to orofacial clefts

Phenotypic heterogeneity is a hallmark of complex traits, and genetic studies may focus on the trait as a whole or on individual subgroups. For example, in orofacial clefting (OFC), three subtypes - cleft lip (CL), cleft lip and palate (CLP), and cleft palate (CP) have been studied separately and in combination. It is more challenging, however, to dissect the genetic architecture and describe how a given locus may be contributing to distinct subtypes of a trait. We developed a framework for quantifying and interpreting evidence of subtype-specific or shared genetic effects in complex traits. We applied this technique to create a \"cleft map\" of the association of 30 genetic loci with three OFC subtypes. In addition to new associations, we found loci with subtype-specific effects (e.g., GRHL3 (CP), WNT5A (CLP)), as well as loci associated with two or all three subtypes. We cross-referenced these results with mouse craniofacial gene expression datasets, which identified promising candidate genes. However, we found no strong correlation between OFC subtypes and expression patterns. In aggregate, the cleft map revealed neither subtype-specific nor shared genetic effects operate in isolation in OFC architecture. Our approach can be easily applied to any complex trait with distinct phenotypic subgroups.

genetics↗

Genome Wide Interaction Studies Identify Sex-Specific Risk Alleles for Nonsyndromic Orofacial Clefts

Nonsyndromic cleft lip with or without cleft palate (NSCL/P) is the most common craniofacial birth defect in humans and is notable for its apparent sexual dimorphism where approximately twice as many males are affected as females. The sources of this disparity are largely unknown, but interactions between genetic and sex effects are likely contributors. We examined gene-by-sex (G x S) interactions in a worldwide sample of 2,142 NSCL/P cases and 1,700 controls recruited from 13 countries. First, we performed genome-wide joint tests of the genetic (G) and G x S effects genome-wide using logistic regression assuming an additive genetic model and adjusting for 18 principal components of ancestry. We further interrogated loci with suggestive results from the joint test (p < 1.00 x 10-5) by examining the G x S effects from the same model. Out of the 133 loci with suggestive results (p < 1.00 x 10-5) for the joint test, we observed one genome-wide significant G x S effect in the 10q21 locus (rs72804706; p = 6.69 x 10-9; OR = 2.62 [1.89, 3.62]) and 16 suggestive G x S effects. At the intergenic 10q21 locus, the risk of NSCL/P is estimated to increase with additional copies of the minor allele for females, but the opposite effect for males. Our observation that the impact of genetic variants on NSCL/P risk differs for males and females may further our understanding of the genetic architecture of NSCL/P and the sex differences underlying clefts and other birth defects.

genetics↗

Investigating the shared genetics of non-syndromic cleft lip/palate and facial morphology

There is increasing evidence that genetic risk variants for non-syndromic cleft lip/palate (nsCL/P) are also associated with normal-range variation in facial morphology. However, previous analyses are mostly limited to candidate SNPs and findings have not been consistently replicated. Here, we used polygenic risk scores (PRS) to test for genetic overlap between nsCL/P and seven biologically relevant facial phenotypes. Where evidence was found of genetic overlap, we used bidirectional Mendelian randomization (MR) to test the hypothesis that genetic liability to nsCL/P is causally related to implicated facial phenotypes. Across 5,804 individuals of European ancestry from two studies, we found strong evidence, using PRS, of genetic overlap between nsCL/P and philtrum width; a 1 S.D. increase in nsCL/P PRS was associated with a 0.10 mm decrease in philtrum width (95% C.I. 0.054, 0.146; P = 0.00002). Follow-up MR analyses supported a causal relationship; genetic variants for nsCL/P homogeneously cause decreased philtrum width. In addition to the primary analysis, we also identified two novel risk loci for philtrum width at 5q22.2 and 7p15.2 in our Genome-wide Association Study (GWAS) of 6,136 individuals. Our results support a liability threshold model of inheritance for nsCL/P, related to abnormalities in development of the philtrum.

genetics↗