Tiger Coat Color Project
Introduction
Tigers are an important keystone predator and a flagship species
for many conservation efforts. There is an under-appreciated
variation in their coat color, which ranges from the standard
orange to white. White tigers are particularly popular at zoos and
exhibits, yet there has been no in-depth studies exploring the
genetic basis of coat color in this remarkable felid. In addition,
genetic information is only now beginning to be incorporated into
the management of captive tigers in the United States. We are
working closely with zoos, wildlife sanctuaries, and private owners
of tigers to study the genomics of tigers and provide
recommendations for scientifically-sound breeding and
management.
Goals
The two primary goals of this project are to understand the
level of genetic diversity harbored in the captive tiger population
and to identify alleles that are responsible for coat color
phenotypes in tigers. The white coat color is inherited recessively
in tigers and is likely due to variation at a single locus. There
are several genes that have been found to affect similar coat
colors in other mammals; among these are those that code for
melanins. These proteins influence the color of skin and fur, can
be split into two major types. Phaeomelanin produces red and yellow
pigments, while eumelanin produces black and brown. Repression of
either of these leads to loss of particular colors; for example,
disruption of the phaeomelanin signaling pathway results in silver
and Burmese coat colors in the domestic cat and the "chinchilla"
color in rodents. Therefore, genes that affect these pathways
likely play a role in the coat color of tigers. We are sequencing
genes that affect these pathways and comparing them between orange
and white tigers. We are also genotyping microsatellites to
understand levels of variation among captive tigers.
Impact
Our research is providing insights into a number of different
aspects of tiger biology and conservation. This complements the
current efforts to conserve genetic diversity of tigers in captive
populations and to improved breeding and management strategies that
will ensure the future health of tigers. If you are interested in
obtaining more information or would like to contribute to our study
please contact Dr. Jan Janecka.
Contact Information
Jan E. Janecka, PhD
Research Assistant Professor (PI)
Department of Veterinary Integrative Biosciences
Texas A&M University
Phone: 979-458-0206
Email: jjanecka@cvm.tamu.edu