Burmese
The Burmese cat is a muscular, social breed with a distinct history, prone to specific genetic health issues like diabetes and head defects.
The Burmese cat is a small-to-medium, muscular breed known for its "brick wrapped in silk" build and dog-like attachment to owners, originating from a single female named Wong Mau brought to the US in 1930. This single ancestor created a genetic bottleneck that persists today, resulting in the second-lowest genetic diversity of any studied cat breed and a unique susceptibility to specific metabolic and structural disorders.
Two standards, one confusing history
Most modern cat registries do not formally recognise the American and British lines as separate breeds, but those that do call the British type the European Burmese. The divergence began when Joseph Cheesman Thompson imported Wong Mau, a dark female cat, from Burma to San Francisco in 1930. Thompson bred her with a Siamese named Tai Mau, and the resulting dark brown kittens formed the foundation of the American strain, which was granted formal recognition by the Cat Fanciers' Association (CFA) in 1936. The British line developed separately, and while the CFA initially suspended recognition due to excessive outcrossing with Siamese cats, it lifted the suspension permanently in 1954. The two versions differ mainly in head and body shape: the British type is slender with a wedge-shaped head, while the American type is stockier with a broader head and shorter muzzle.
Appearance and the "brick wrapped in silk" myth
Burmese cats are a small to medium breed, typically weighing 4–6 kg (9–13 lb), but they are substantially built and muscular. They should feel heavy for their size when held, a texture often described as "a brick wrapped in silk". The coat is very short, fine, and glossy with a satin-like finish, and the colour must be solid and uniform over the body. The original standard colour is a rich dark brown, genetically black, known as sable in the USA, brown in the UK, or seal in New Zealand. This specific colour is the result of the Burmese gene (cbcb), which reduces pigment production, converting black into warm brown on the torso and rendering all other coat colours paler than usual. While the breed was originally limited to dark brown, it is now available in a wide variety of sepia colours, including blue, chocolate, lilac, red, and cream, with some registries also recognising cinnamon and fawn variants.
Behaviour that mimics a dog
Burmese are a notably people-oriented breed that maintains kitten-like energy and playfulness well into adulthood. They form strong bonds with their owners and gravitate toward human activity, often learning games like fetch and tag. Veterinary observations note that their dog-like attachment causes a greater dependence on human contact compared to the tolerant acceptance of human company seen in other breeds. They are persistently vocal, with a softer, sweeter voice reminiscent of their Siamese ancestry, but they are not independent enough to be left alone for extended periods. This high social need means they require constant interaction and are not suited for owners who are away from home for long stretches.
Genetic diversity and the single ancestor problem
A 2008 study led by feline geneticist Dr Leslie Lyons at UC Davis found that the American Burmese has the second lowest level of genetic diversity of all breeds studied, trailing only the Singapura. The CFA reports that breeders are increasingly seeing less hearty litters, smaller adults, and immune system problems, pointing to inbreeding depression becoming more common. To address this, the Burmese breed council currently allows outcrossing using Bombay, Tonkinese, and Burmese type cats imported from Southeast Asia. The lineage of American Burmese cats also hosts a specific 4-aminoacid deletion on the ALX1 gene. Heterozygosity of this mutation results in brachycephaly, while homozygosity results in a profound head malformation known as the Burmese head defect, which is always fatal.
Health risks and life expectancy
Despite the genetic challenges, the Burmese has a high average life expectancy. A study of veterinary records in the UK found an average life expectancy of 14.42 years for the breed, which is higher than the overall average of 11.74 years. However, they are prone to specific conditions that require monitoring. A 2016 study in England found the Burmese to have a higher prevalence of diabetes mellitus, with 2.27% of the breed affected compared to an overall rate of 0.58%. An Australian study in 2009 found an even higher prevalence of 22.1% compared to an overall rate of 7.4%. The breed is also the most commonly affected for feline orofacial pain syndrome (FOPS), an acute teething disorder in young kittens where the eruption of second teeth causes extreme discomfort and self-mutilation. Other predispositions include congenital hypotrichosis, gangliosidosis 2, and hypokalaemia, the latter being the condition the breed is most often affected by, caused by a mutation in the WNK4 gene.