My reaction to the title is to think, “Hmm. Who has been going around claiming that “it sometimes skips a generation” was an explanation?”
I would say that “it sometimes skips a generation” is an observation. The same observation can be made about many traits, so it may also be called a categorization, or a recognition of a pattern. It’s not a causal explanation, although it might be taken to hint at one: “maybe a thing that causes these other skips-a-generation phenomena also causes this one”. If someone doesn’t know that a trait is X-linked, or doesn’t know what chromosomes are, then “it sometimes skips a generation” may be the most they can say.
(Incidentally, a non-X-linked recessive trait may also be seen to “skip a generation” if it’s common enough that one carrier has a decent chance of marrying another carrier. If you have enough good data, you can distinguish X-linked recessive from autosomal recessive.)
I totally agree, technically it’s a correct observation, but it’s also what I was taught by adults when I asked as a kid, and therefore I wanted to correct it as the real explanation is very short and concise.
Ah, that explains it. Adults are often not very good at explaining science to kids. And I’d guess the adults in question might not have known that colorblindness was X-linked, even if they were paid to teach science; I think I’d only be surprised by that ignorance in K-12 education if a teacher chose to present the subject of colorblind genetics to the class.
I once had a doctor (I’d guess in her early thirties) who, in a discussion of male-pattern baldness, mentioned the mother’s father as the best data point—which means it must be X-linked, because otherwise the father’s father would be an equally good data point (not to mention the father, if old enough). I said, “So, it’s X-linked, then.” She said, “No, it’s not X-linked”. I stated the above logic. She didn’t comment on it, but consulted her computer system, and reported that there were five genes found to be associated with male-pattern baldness, some on the X chromosome and some not.
I think this was by parents, so they are forgiven :), your story is pretty crazy, but there is so much to know as a doctor that most becomes rules of thumbs (maps vs buttons) untill called out like you did
My reaction to the title is to think, “Hmm. Who has been going around claiming that “it sometimes skips a generation” was an explanation?”
I would say that “it sometimes skips a generation” is an observation. The same observation can be made about many traits, so it may also be called a categorization, or a recognition of a pattern. It’s not a causal explanation, although it might be taken to hint at one: “maybe a thing that causes these other skips-a-generation phenomena also causes this one”. If someone doesn’t know that a trait is X-linked, or doesn’t know what chromosomes are, then “it sometimes skips a generation” may be the most they can say.
(Incidentally, a non-X-linked recessive trait may also be seen to “skip a generation” if it’s common enough that one carrier has a decent chance of marrying another carrier. If you have enough good data, you can distinguish X-linked recessive from autosomal recessive.)
I totally agree, technically it’s a correct observation, but it’s also what I was taught by adults when I asked as a kid, and therefore I wanted to correct it as the real explanation is very short and concise.
Ah, that explains it. Adults are often not very good at explaining science to kids. And I’d guess the adults in question might not have known that colorblindness was X-linked, even if they were paid to teach science; I think I’d only be surprised by that ignorance in K-12 education if a teacher chose to present the subject of colorblind genetics to the class.
I once had a doctor (I’d guess in her early thirties) who, in a discussion of male-pattern baldness, mentioned the mother’s father as the best data point—which means it must be X-linked, because otherwise the father’s father would be an equally good data point (not to mention the father, if old enough). I said, “So, it’s X-linked, then.” She said, “No, it’s not X-linked”. I stated the above logic. She didn’t comment on it, but consulted her computer system, and reported that there were five genes found to be associated with male-pattern baldness, some on the X chromosome and some not.
I think this was by parents, so they are forgiven :), your story is pretty crazy, but there is so much to know as a doctor that most becomes rules of thumbs (maps vs buttons) untill called out like you did