BLACK TIGERS

Sept. 18, 2021

A team of scientists from the National Centre for Biological Sciences (NCBS), Bangalore has resolved the genetic mystery of Simlipal’s so-called black tigers.

About:

  • The study found that a single genetic mutation in these tigers caused black stripes to broaden or spread into the tawny background.

  • Tigers have a distinctive dark stripe pattern on a light background of white or golden.

  • A rare pattern variant, distinguished by stripes that are broadened and fused together, is also observed in both wild and captive populations.

  • This is known as pseudo-melanism, which is different from true melanism, a condition characterised by unusually high deposition of melanin, a dark pigment.

  • While truly melanistic tigers are yet to be recorded, pseudo-melanistic ones have been camera-trapped repeatedly, and only, in Simlipal, a 2,750-km tiger reserve in Odisha, since 2007.

  • Through whole-genome data and pedigree-based association analyses from zoo tigers, the study found that pseudo-melanism is linked to a single mutation in Transmembrane Aminopeptidase Q (Taqpep), a gene responsible for similar traits in other cat species.