Zoe, the cosy One, born on 31 May 05, died of HCM/aortic thrombosis in mid-July 06; she was only 13 months old.
Zoe's father died at the age of 1 year; he was not my male and was not owned by me
Zoe's mother is healthy and was scanned heart-healthy in August 06
It used to be thought that HCM was inherited exclusively in an autosomal dominant way, which means
it is enough for one parent to carry the defective gene for the disease or defect to appear.......... according to Mendel's laws, about half of the offspring are then affected by this hereditary disease and fall ill, while the other half are heterozygous carriers of the disease.
A distinction is made between homozygous animals, meaning both parents carry the gene, and heterozygous animals, meaning only one parent carries the defective gene
Today we know that HCM can also be passed on in an autosomal recessive and polygenic way.
Causes of HCM can be an overactive thyroid, high blood pressure (usually combined with kidney disease) or a genetic predisposition in certain breeds.
For the Maine Coon, an autosomal dominant mode of inheritance with complete penetrance is assumed. Males are affected more often than females, and symptoms usually appear from the 3rd year of life.
For the Sacred Birman, a genetic test is not yet possible, so it is also not possible to identify homozygous/heterozygous animals.
The only way to be reasonably sure is to have the cats scanned! However, keep in mind that a single scan is not conclusive, as the disease can appear at any age.
An examination of breeding cats from the age of 2 years is recommended. The examination should then be repeated every 2 years.
Here is some information about the HCM/RCM study in Birmans in Sweden
since I bought a male in Sweden in 2009 and was able to talk personally with several Swedish Birman breeders at the FIFé World Show 2009 in St. Gallen, I learned that Sweden has an HCM/RCM health programme for Birmans, supported by the Swedish Birman club and the Swedish Ministry of Agriculture.
Unfortunately I don't speak Swedish, here is the original link http://www.birma.se/halsa/halsoprogram-hjarta.htm
Here I would like to go into some genetic defects that also occur in Birman breeding (autosomal recessive inheritance), which means that with this mode of inheritance both parents carry the responsible gene!
unfortunately, so-called autosomal recessive genetic faults such as kinked tails, squinting and nystagmus sometimes occur in Birmans too. This takes nothing away from the charm of these wonderful cats and is usually not important for the cat or its owner,
as long as these cats are not used for breeding...
Genetic defects such as kinked tail, chin spot, squinting and nystagmus are inherited in an autosomal recessive way, i.e. if such a kitten is born, both parents are carriers of this defective gene...
such defective genes can be carried hidden over many generations.
I do not breed with cats that show a defect such as squinting, nystagmus, kinked tail or chin spot.....
I do not sell cats with such defects for breeding.
I am honest, even if it sometimes harms me :-)))
I cannot promise a cat owner who brings her female to my stud that the defects mentioned above will not appear in a mating, because I cannot know for how many generations my male has been carrying genetic defects unknown to me..... likewise, I cannot promise this to the buyer of a breeding cat from my cattery..... nobody can.
Here is a list
autosomal dominant means it is enough for one parent to carry the defective gene for the disease or defect to appear.......... according to Mendel's laws, about half of the offspring are then affected by this hereditary disease and fall ill, while the other half are heterozygous carriers of the disease.
a distinction is made between homozygous animals, meaning both parents carry the gene, and heterozygous animals, meaning only one parent carries the defective gene
here is a list of some diseases that can be inherited dominantly
Important links on this topic:
http://www.tierkardiologie.lmu.de/pta/hypertrophe-kardiomyopathie.html ....hier lasse ich meine Katzen schallen
Heart specialists are listed here
http://www.collegium-cardiologicum.de/
If you have questions about HCM
Here is a link to an HCM forum: Moderator: DR. Wess
http://www.tierkardiologie.lmu.de/sys/cgi/yabb2/YaBB.pl
When the time comes, my cats will undergo a cardiac ultrasound examination at the LMU München.