Uniparental IsoDisomy: a case study on a new mechanism of Friedreich ataxia.

Friedreich's Ataxia (FRDA) is the most common hereditary ataxia and is mainly caused by biallelic GAA repeat expansion in the FXN gene. Rare patients carrying FXN point mutations or intragenic deletions are reported. We describe the first FRDA patient with a chromosome 9 segmental Uniparental isoDisomy (UPiD) unmasking a homozygous FXN expansion initially undetected by TP-PCR.

Increased attention allocation to stimuli reflecting end-states of compulsive behaviors among obsessive compulsive individuals.

Attentional research in OCD has focused solely on threat stimuli, assumed to provoke related obsessions and ensuing compulsions. OCD-related stimuli depicting the completion of compulsive acts ("end-states") have yet to be examined. Past research also neglected to explore the reliability of tasks used.

OTC deficiency in females: Phenotype-genotype correlation based on a 130-family cohort.

OTC deficiency, an inherited urea cycle disorder, is caused by mutations in the X-linked OTC gene. Phenotype-genotype correlations are well understood in males but still poorly known in females. Taking advantage of a cohort of 130 families (289 females), we assessed the relative contribution of OTC enzyme activity, X chromosome inactivation, and OTC gene sequencing to genetic counseling in heterozygous females.

A retrospective study on the efficacy of prenatal diagnosis for pregnancies at risk of mitochondrial DNA disorders.

Purpose: Prenatal diagnosis of mitochondrial DNA (mtDNA) disorders is challenging due to potential instability of fetal mutant loads and paucity of data connecting prenatal mutant loads to postnatal observations. Retrospective study of our prenatal cohort aims to examine the efficacy of prenatal diagnosis to improve counseling and reproductive options for those with pregnancies at risk of mtDNA disorders.

Methods: We report on a retrospective review of 20 years of prenatal diagnosis of pathogenic mtDNA variants in 80 pregnant women and 120 fetuses.

Improving post-natal detection of mitochondrial DNA mutations.

Introduction: Currently, genetic testing of mitochondrial DNA mutations includes screening for single-nucleotide variants, several base pair insertions or deletions, large-scale deletions, or relative depletion of total mitochondrial DNA content. Within the last decade, next-generation sequencing (NGS) has resulted in remarkable advances in the field of mitochondrial diseases (MD) and has become a routine step of the diagnostic workup.

Areas Covered: We aimed to present an overview of current technologies employed in molecular diagnosis of mitochondrial DNA diseases.