The Bombay was developed by Nikki Horner, a breeder in Louisville, Kentucky. She set out to create a "miniature black panther" by crossing sable Burmese with a solid black American Shorthair. Her first attempts in the late 1950's were disappointing. A few years later, working with different breeding stock, she began to get the results that she was looking for: a cat with good muscular development and a very short, close-lying black coat. Recognition and acceptance of the new breed by the registering associations took 18 years; the Bombay was accepted for championship in CFA in 1976
Bombay breeders frequently outcross to Burmese to retain the body type and coat texture. Almost no one outcrosses to American Shorthair any more, because it is very easy to maintain the (dominant) black color in the Bombay lines and such outcrosses would usually result in undesirable body type. Some associations no longer permit outcrossing to American Shorthair.
As a consequence, the Bombay shares many physical characteristics with the Burmese. Nikki Horner considers the Bombay a "black Burmese", but other breeders point out the physical differences. Bombays tend to be a little larger, with longer bodies and longer legs than the Burmese, and have a less pronounced nose break
The gene for the black coat is dominant, but many Bombays still carry the sable color as a recessive. A sable-colored kitten may appear in a litter from a Bombay x Bombay breeding. If both of the parents are heterozygous for black, one in four kittens will be sable, on average. A Bombay x Burmese breeding will frequently produce some sable kittens along with the black ones
These "sable Bombays" are generally sold as pets, since they cannot be shown as Bombays. One association, TICA, allows these kittens to be registered and shown as sable Burmese, but the Bombay body type is sufficiently different from Burmese that they generally are not show quality. However, a person looking for a pet Burmese might do well to contact Bombay breeders, since only a trained eye would notice the differences between a "sable Bombay" and a pure Burmese
The Bombay breed also shares an unfortunate trait with the Burmese. The "Burmese Craniofacial Defect" is a genetic disorder that affects the development of the skull in the fetus. Occasionally, kittens from lines that carry this defect will be born with severely deformed heads and must be euthanized at birth. The mode of inheritance of this anomaly is still poorly understood. The defect is of no concern to pet owners because it only affects newborns, but anyone who is considering breeding Bombays or Burmese and who is unwilling to deal with this defect must perform extensive pedigree research to find bloodlines that are free of the defect. A few lines of "traditional" Bombays and Burmese that are free of the defect do exist today. This is a complex and emotionally-charged issue among Burmese and Bombay breeders. Anyone who is interested in this subject should obtain the published research and should not rely on hear