Medicine and Health Sciences Commons^™

Brain Function Distinguishes Female Carriers And Non-Carriers Of Familial Risk For Autism, Adam T Eggebrecht, Ally Dworetsky, Zoë Hawks, Rebecca Coalson, Babatunde Adeyemo, Savannah Davis, Daniel Gray, Alana Mcmichael, Steven E Petersen, John N Constantino, John R Pruett

2020-Current year OA Pubs

BACKGROUND: Autism spectrum disorder (ASD) is characterized by high population-level heritability and a three-to-one male-to-female ratio that occurs independent of sex linkage. Prior research in a mixed-sex pediatric sample identified neural signatures of familial risk elicited by passive viewing of point light motion displays, suggesting the possibility that both resilience and risk of autism might be associated with brain responses to biological motion. To confirm a relationship between these signatures and inherited risk of autism, we tested them in families enriched for genetic loading through undiagnosed ("carrier") females.

METHODS: Using functional magnetic resonance imaging, we examined brain responses to passive …

De Novo And Bi-Allelic Pathogenic Variants In Nars1 Cause Neurodevelopmental Delay Due To Toxic Gain-Of-Function And Partial Loss-Of-Function Effects, Andreea Manole, Marwan Shinawi, Marisa V. Andrews, Dustin Baldridge, John F. Mantovani, Et Al.

2020-Current year OA Pubs

Aminoacyl-tRNA synthetases (ARSs) are ubiquitous, ancient enzymes that charge amino acids to cognate tRNA molecules, the essential first step of protein translation. Here, we describe 32 individuals from 21 families, presenting with microcephaly, neurodevelopmental delay, seizures, peripheral neuropathy, and ataxia, with de novo heterozygous and bi-allelic mutations in asparaginyl-tRNA synthetase (NARS1). We demonstrate a reduction in NARS1 mRNA expression as well as in NARS1 enzyme levels and activity in both individual fibroblasts and induced neural progenitor cells (iNPCs). Molecular modeling of the recessive c.1633C>T (p.Arg545Cys) variant shows weaker spatial positioning and tRNA selectivity. We conclude that de novo and …

On The Nature Of Monozygotic Twin Concordance And Discordance For Autistic Trait Severity: A Quantitative Analysis, Lauren Castelbaum, Chad M Sylvester, Yi Zhang, Qiongru Yu, John N Constantino

2020-Current year OA Pubs

The characterizing features of autism spectrum disorder (ASD) are continuously distributed in nature; however, prior twin studies have not systematically incorporated this knowledge into estimations of concordance and discordance. We conducted a quantitative analysis of twin-twin similarity for autistic trait severity in three existing data sets involving 366 pairs of uniformly-phenotyped monozygotic (MZ) twins with and without ASD. Probandwise concordance for ASD was 96%; however, MZ trait correlations differed markedly for pairs with ASD trait burden below versus above the threshold for clinical diagnosis, with R

Three-Dimensional Facial Morphology In Cantú Syndrome, Helen I Roessler, Kathleen Shields, Dorothy K Grange, Nine V A M Knoers, Gijs Van Haaften, Peter Hammond, Mieke M Van Haelst

2020-Current year OA Pubs

Cantú syndrome (CS) was first described in 1982, and is caused by pathogenic variants in ABCC9 and KCNJ8 encoding regulatory and pore forming subunits of ATP-sensitive potassium (K

Prevalence Of Clinically Actionable Disease Variants In Exceptionally Long-Lived Families, Paige Carlson, Mary K Wojczynski, Todd Druley, Joseph H Lee, Joseph M Zmuda, Bharat Thyagarajan

2020-Current year OA Pubs

BACKGROUND: Phenotypic expression of pathogenic variants in individuals with no family history of inherited disorders remains unclear.

METHODS: We evaluated the prevalence of pathogenic variants in 25 genes associated with Mendelian-inherited disorders in 3015 participants from 485 families in the Long Life Family Study (LLFS). Boot-strapping and Fisher's exact test were used to determine whether allele frequencies in LLFS were significantly different from the allele frequencies reported in publicly available genomic databases.

RESULTS: The proportions of pathogenic autosomal dominant mutation carriers in BRCA1 and SDHC in LLFS study participants were similar to those reported in publicly available genomic databases (0.03% …

Polr1b And Neural Crest Cell Anomalies In Treacher Collins Syndrome Type 4, Elodie Sanchez, Tomi L Toler, Walton Nephi, Marcia Willing, Et Al.

2020-Current year OA Pubs

PURPOSE: Treacher Collins syndrome (TCS) is a rare autosomal dominant mandibulofacial dysostosis, with a prevalence of 0.2-1/10,000. Features include bilateral and symmetrical malar and mandibular hypoplasia and facial abnormalities due to abnormal neural crest cell (NCC) migration and differentiation. To date, three genes have been identified: TCOF1, POLR1C, and POLR1D. Despite a large number of patients with a molecular diagnosis, some remain without a known genetic anomaly.

METHODS: We performed exome sequencing for four individuals with TCS but who were negative for pathogenic variants in the known causative genes. The effect of the pathogenic variants was investigated in zebrafish.

RESULTS: …