I endeavour to answer the question as to why Burmese cats are 5 times more likely than other breeds to develop Type II diabetes? The general view is that Burmese cats are about 5 times more likely than other cat breeds to develop Type II diabetes (diabetes mellitus). One study says that the predisposition to type II diabetes in Burmese cats is geographically located in places where it also affects humans. In other words, this study is saying that Type II diabetes in cats runs in parallel with type II diabetes in people in Australia, New Zealand and Europe. Is this linkage to do with obesity in people resulting in obesity in their cat which in turn can lead to Type II diabetes?
I’m speculating. However, one reason why Burmese cats are predisposed to developing Type II diabetes is because they have a decreased sensitivity to the effects of the hormone insulin. This results in an increased level of sugar in the blood and a commensurate lowering of uptake of glucose into the cells. As I understand it, “decreased sensitivity to insulin” means insulin resistance.
In other words, the body does not respond to insulin in a normal way which means that it does not have the same effect in controlling glucose in the body. This results in elevated levels of glucose in the blood which damages certain organs such as the kidney (damages the blood vessels), liver (fatty liver disease) and the nervous system at the extremities as I understand it.
So why is there a decreased sensitivity to the effects of insulin in Burmese cats? A further study which I list below tells us that the Burmese cats in the study “had higher insulin and lower adiponectin concentrations than Maine Coon cats”. “Adiponectin” is a protein hormone involved in regulating glucose levels.
The study also found that the pattern of substances formed and which are necessary for metabolism in the Burmese cat (metabolites) were similar to those in people with insulin resistance. In other words, the metabolic profile of Burmese cats predisposes them to Type II diabetes.
The scientists suggested that it might be possible to detect an abnormal level of low molecular weight metabolites produced in cells during metabolism as an indicator that the cat has become insulin resistant.
My research did not tell me why Burmese cats have, on my understanding, irregular levels of metabolites and lower adiponectin concentrations. However, there appears to be one possibility which is inbreeding depression due to selective breeding which has gone too far which reduces genetic diversity to the point where the immune system is compromised.
Or it has been suggested that the Australian Burmese cat might suffer from a genetic mutation in a single gene which might be responsible for this insulin resistance. This mutation may have come into existence because of over-zealous inbreeding (my thought). Remember that all purebred cats are inbred. It’s part and parcel of the process of artificial selection. And selective breeding can lead to the emergence of damaging recessive genes which are normally hidden.
This genetic mutation might have an impact on the metabolism of glucose which could lead to insulin resistance, or reduced glucose tolerance. There appears to be a question mark whether this mutation is present in all Australian Burmese cats or just those exposed to environmental factors such as obesity.
I hope this helps a bit. I sense that this is work on progress.
Study referred to: Differences in metabolic profiles between the Burmese, the Maine coon and the Birman cat—Three breeds with varying risk for diabetes mellitus.
