A unique single nucleotide polymorphism in Agouti Signalling Protein (ASIP) gene changes coat colour of Sri Lankan Leopard (Panthera pardus kotiya) to dark black

Abstract

ABSTRACTThe Sri Lankan Leopard (Panthera pardus kotiya) is an endangered subspecies restricted to isolated and fragmented populations in Sri Lanka. Among them, the melanistic leopards have been recorded on rare occasions. The existing literature suggests that melanism evolved several times in the Felidae family, with three separate species revealing distinct mutations. Nevertheless, the mutations in the remaining species, including Sri Lankan black leopard, are unknown. We used reference-based assembled the nuclear genomes of Sri Lankan normal and black leopard and de novo assembled mitogenomes of the same to investigate the genetic basis, adaptive significance, and evolutionary history of the Sri Lankan black leopard. Our data suggested coalescence time of Sri Lankan regular and black leopards at ∼0.5 Million years, sisters to Panthera pardus lineage. Interestingly, in the black leopard, a single nucleotide polymorphism in exon-4 possibly completely ablates Agouti Signaling Protein (ASIP) function. Existing genomic data suggest new a species-specific mutation of the ASIP gene in the Felidae family, contributing to naturally occurring colouration polymorphism. As such, the Sri Lankan black leopard and normal leopard probably evolved from the same ancestor, while the mutation in the ASIP gene resulted in black coat colour. This rare mutation could be adaptable to the environment that back leopards reported, camouflage, with a likelihood of recurrence and transmission to future generations. However, protecting this sensitive environment is critical for the conservation of the existing populations and providing breeding grounds.