There are no genetic screeners for HCM in sphynx but the breed certainly
has HCM in some lines. Breeders tend to scan at about age 3 when HCM can
start to show but as someone else said, the disease can show much later once
they had kittens. I would, without any doubt whatsoever, have your Sphynx
scanned for HCM now they have reached over 3. I know people are working to try
and find the genetic tests like they have for Maine Coone, but even with
those, they only pick up the common type.
I`m not sure where you are, but if UK, there is a screening programme for
pedigree cats at reduced cost where they just do the HCM scan (see FAB cats,
I can find the link if needed) and if clear you get a certificate which
lasts for a year.
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