Hi boyz'n'gurlz,
My wee sister has now been diagnosed(?) with haemochromatosis. I had a phone call with her earlier and she said she was "homozygous" and a carrier. To the best of my knowledge this isn't possible as a carrier is always heterozygous. Is this correct?
A carrier means you only have one copy of the gene. Homozygous and heterozygous mean you have two copies. Homo means you have the same gene ie you have two C282Y and Hetero means you have two genes but they are different, ie one C282Y and one H63D. HTH
I was under the impression heterozygous would mean she was Hh(carrier) while homozygous would mean she was either HH(clear) or hh(affected)
Homozygous means she has two copies of the same HFE mutation. Heterozygous means you have only one HFE gene. Compound heterozygous means you have one type of HFE gene and one different type of HFE gene, e.g. C282Y/H63D.
Of course, whether you are homozygous or heterozygous, you are a 'carrier', because either way, homozygous means you will definitely pass on the gene to offspring, and heterozygous means there is a 50/50 chance of passing on the gene to offspring.
As your sister has inherited these genes from both her mother and father, then I hope, you have been tested.
HH, Hh, hh - all means the same thing - hereditary haemochromatosis - not varying degrees of haemochromatosis.