Investigation of the association of the MLPH gene with seasonal canine flank alopecia in Rhodesian Ridgeback dogs

Canine flank alopecia (CFA) is a skin condition in dogs characterized by non-inflammatory, seasonally recurring episodes of localized hair loss and often hyperpigmentation of the affected skin. A genetic basis is suspected because of the predisposition in certain breeds, such as the Rhodesian Ridgeback (RR). This study investigated the possible role of the canine melanophylin (MLPH) gene in CFA among RRs through pedigree analysis and MLPH genotyping.

We included 24 CFA-affected and 12 non-CFA-affected control RRs. Pedigree analysis revealed inbreeding loops and close family relationships among the CFA-affected dogs, indicating the potential heritability of CFA. MLPH genotyping revealed 3/24 (12.5%) affected dogs and 1/12 (8.3%) control dogs to be heterozygous (Dd) for the dilute (d) allele, indicating no difference between these groups. None of the dogs were found to be homozygous (dd). Statistical analysis did not reveal an association between the MLPH-d allele and CFA.

The familial patterns among affected RRs observed through pedigree analysis suggest a potential genetic component in CFA. However, our findings from the MLPH genotyping did not reveal that the MLPH gene is involved in this skin condition in RRs. However, further genetic studies are needed to clarify the etiology of CFA in RR dogs.