Affiliation:
1. Department of Clinical Genetics Odense University Hospital Odense Denmark
2. Department of Clinical Research University of Southern Denmark Odense Denmark
3. European Reference Network for Rare Skin Diseases (ERN‐Skin) Odense Denmark
4. Hudklinikken Kolding Kolding Denmark
Abstract
AbstractPalmoplantar keratoderma (PPK) is a heterogeneous group of rare skin diseases characterized by hyperkeratosis on the palms or soles. The subtype isolated punctate PPK is caused by heterozygous variants in AAGAB. We investigated if the variant AAGAB c.370C>T, p.Arg124Ter in patients with punctate PPK in the Region of Southern Denmark represented a founder variant and estimated the age to the most recent common ancestor. We performed haplotype analysis on samples from 20 patients diagnosed with punctate PPK and the AAGAB c.370C>T, p.Arg124Ter variant. Using the Gamma Method, we calculated the years to the most recent common ancestor. We also explored the presence of the variant in other populations through literature and databases (HGMD, ClinVar, and gnomAD). Our analysis revealed a shared haplotype of 3.0 Mb, suggesting shared ancestry. The ancestral haplogroup was estimated to an age of 12.1 generations (CI: 4.9–20.3) equivalent to approximately 339 years (CI: 137–568). This study confirms that the frequently observed variant AAGAB c.370C>T, p.Arg124Ter in punctate PPK among patients in the Region of Southern Denmark is caused by a founder variant. We recommend testing for the variant as initial screening in our region and potentially for all Danish patients presenting with punctate PPK.
Funder
Region Syddanmark
Odense Universitetshospital
Robert Wehnerts og Kirsten Wehnerts Fond
Kongelig Hofbuntmager Aage Bangs Fond
Fonden for Faglig Udvikling af Speciallægepraksis
Syddansk Universitet