U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PubAg

Main content area

Compound heterozygous PLA2G6 loss-of-function variants in Swaledale sheep with neuroaxonal dystrophy

Author:
Anna Letko, Ben Strugnell, Irene M. Häfliger, Julia M. Paris, Katie Waine, Cord Drögemüller, Sandra Scholes
Source:
Molecular genetics and genomics 2021 v.296 no.1 pp. 235-242
ISSN:
1617-4615
Subject:
chromosomes, etiology, exons, gait, genomics, genotyping, heterozygosity, histopathology, introns, loss-of-function mutation, neurodegenerative diseases, pedigree, phenotype, purebreds
Abstract:
Sporadic occurrences of neurodegenerative disorders including neuroaxonal dystrophy (NAD) have been previously reported in sheep. However, so far no causative genetic variant has been found for ovine NAD. The aim of this study was to characterize the phenotype and the genetic aetiology of an early-onset neurodegenerative disorder observed in several lambs of purebred Swaledale sheep, a native English breed. Affected lambs showed progressive ataxia and stiff gait and subsequent histopathological analysis revealed the widespread presence of axonal spheroid indicating neuronal degeneration. Thus, the observed clinical phenotype could be explained by a novel form of NAD. After SNP genotyping and subsequent linkage mapping within a paternal half-sib pedigree with a total of five NAD-affected lambs, we identified two loss-of-function variants by whole-genome sequencing in the ovine PLA2G6 gene situated in a NAD-linked genome region on chromosome 3. All cases were carriers of a compound heterozygous splice site variant in intron 2 and a nonsense variant in exon 8. Herein we present evidence for the occurrence of a familial novel form of recessively inherited NAD in sheep due to allelic heterogeneity at PLA2G6. This study reports two pathogenic variants in PLA2G6 causing a novel form of NAD in Swaledale sheep which enables selection against this fatal disorder.
Agid:
7256400