I’d heard a while ago that the photic sneeze reflex was a so-called Mendelian trait which might actually be a “simple Mendelian trait”. Having found so many other cases where such claims didn’t pan out, I guess at this point I shouldn’t be very surprised when another “simple Mendelian inheritance” story turns out to be complicated :-P
I only read the abstract of your linked study rather than methods and everything. Out of curiosity (if you read the whole thing), did they disentangle the causal factors behind variation in the trait? Like, did they distinguish between hypotheses such as “actual non-ACHOO-carriers can acquire the reflex based on life experience” vs “only carriers can acquire the trait, but penetrance increases with age, giving the potentially false appearance of people acquiring it based purely on environmental factors”?
I am trying to access the full article through my library system but it will take some time. It is worth noting that my goal is for light to make me sneeze, if and only if I already feel like sneezing. This is different from ACHOO syndrome as generally described; so I am unsure whether my technique uses the same biological mechanism.
EDIT: Until reading your post I had not considered the possibility that I may be a carrier who had not yet expressed this trait. I thought that I would be able to acquire it through conditioning regardless. Lack of a response from my family suggests that this is an acquired trait for me.
UPDATE: Indeed, http://www.ncbi.nlm.nih.gov/pubmed/7673597 was about to discriminate between this hypotheses. I have the article and it states that 39.3% of those affected reported no family history of photic sneezing. From this and other data they conclude that ”… in approximately 25% of cases the [photic sneeze response] may be inherited in an autosomal dominant manner, but the majority of cases appear to be related to environmental influences.” They did not identify any causal environmental factors for the formation of this response, but that it is primarily acquired is good news for anyone interested in trying it.
I’d heard a while ago that the photic sneeze reflex was a so-called Mendelian trait which might actually be a “simple Mendelian trait”. Having found so many other cases where such claims didn’t pan out, I guess at this point I shouldn’t be very surprised when another “simple Mendelian inheritance” story turns out to be complicated :-P
I only read the abstract of your linked study rather than methods and everything. Out of curiosity (if you read the whole thing), did they disentangle the causal factors behind variation in the trait? Like, did they distinguish between hypotheses such as “actual non-ACHOO-carriers can acquire the reflex based on life experience” vs “only carriers can acquire the trait, but penetrance increases with age, giving the potentially false appearance of people acquiring it based purely on environmental factors”?
I am trying to access the full article through my library system but it will take some time. It is worth noting that my goal is for light to make me sneeze, if and only if I already feel like sneezing. This is different from ACHOO syndrome as generally described; so I am unsure whether my technique uses the same biological mechanism.
EDIT: Until reading your post I had not considered the possibility that I may be a carrier who had not yet expressed this trait. I thought that I would be able to acquire it through conditioning regardless. Lack of a response from my family suggests that this is an acquired trait for me.
UPDATE: Indeed, http://www.ncbi.nlm.nih.gov/pubmed/7673597 was about to discriminate between this hypotheses. I have the article and it states that 39.3% of those affected reported no family history of photic sneezing. From this and other data they conclude that ”… in approximately 25% of cases the [photic sneeze response] may be inherited in an autosomal dominant manner, but the majority of cases appear to be related to environmental influences.” They did not identify any causal environmental factors for the formation of this response, but that it is primarily acquired is good news for anyone interested in trying it.