How do you tell if a disorder is SEX-Linked
Started by axp107
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F
Foghorn
For sex-linked
Assuming father carries normal/wild type sex chromosomes
X dominant with XX mom (she has the disorder) ----> all progeny get it (the disorder)
X dominant with Xx mom (she has the disorder) ------> half of all progeny get it
x recessive with Xx mom (unaffected) ------>female progeny are normal, half of males get it
x recessive with xx mom (affected)-------->female progeny are normal, all of males get it
You can make up other scenarios where the father carries the abnormal chromosome that's dominant/recessive. And also do F1, F2 etc generations.
the big giveaway that I usually see is if you see a majority of one sex getting the disease, i.e. usually males since they only get one copy of the X chromosome and 1 of Y.
hence they have a higher probability of expressing a sex-linked trait. their mother usually doesn't express the disease since she has 2 copies of X chromosomes, and if its recessive, her dominant copy will prevent her from expressing the disorder.
I dunno about sex-linked dominant traits, i'm sure they're out there but I've never heard anything about it.
sorry if this doesn't make sense, i'm pretty tired lol 😴
edit: just saw foghorn's post...great summary of the possibilities
hence they have a higher probability of expressing a sex-linked trait. their mother usually doesn't express the disease since she has 2 copies of X chromosomes, and if its recessive, her dominant copy will prevent her from expressing the disorder.
I dunno about sex-linked dominant traits, i'm sure they're out there but I've never heard anything about it.
sorry if this doesn't make sense, i'm pretty tired lol 😴
edit: just saw foghorn's post...great summary of the possibilities
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Prominent calluses on the hands and "chafing of the willy".
Well said.
Prominent calluses on the hands and "chafing of the willy".
Well said.
Just to elaborate, there are two more cases (which don't assume that the father is normal!):
X dominant with X father (he has the disorder) ----> Daughters get it (the disorder)
X recessive with xx father (he has the disorder) and Xx mother (she seems normal) ----> half female progeny have it, half males have it (the disorder)
X dominant with X father (he has the disorder) ----> Daughters get it (the disorder)
X recessive with xx father (he has the disorder) and Xx mother (she seems normal) ----> half female progeny have it, half males have it (the disorder)
