VOORHEES, N.J. (CBS) -- One kitten in New Jersey is a genetic anomaly.
Dr. Erin Henry, a veterinarian at the Animal Welfare Association in Voorhees, discovered that a 3-week-old orange and black tortoiseshell kitten named Burrito was a boy.
Only one in 3,000 of those types of cats are male, according to a 2012 study by the College of Veterinary Medicine at the University of Missouri.
"When I turned little Burrito over I was so surprised," said Henry. "I've examined thousands of kittens while working at AWA and they are so rare that he may be the only male tortoiseshell I'll ever see again."
According to the Animal Welfare Association, a cat's orange and black fur is dictated by the X chromosome. Females have two X chromosomes, while males have an XY combination, which means that only female cats can have that color fur. However, to be a male tortoiseshell cat, he must have two X chromosomes and one Y.
Cats born with the extra sex chromosome don't have developmental issues, but they tend to be sterile.
Burrito will be put up for adoption when he's 8 weeks old.
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