Posted by alexandra_k on September 7, 2013, at 1:07:59
In reply to Re: Blood Type association, posted by alexandra_k on September 7, 2013, at 0:57:37
the problem seems to be to identify the 'characters' and the 'traits'.
e.g., mendel studied pea plants. the 'characters' he studied were: flower color. seed color. pod color. pod shape. etc. and the 'traits' are the variants of the characters. so purple or white (flower color). green or yellow (seed color).
mendel was a lucky lucky man that he picked pea plants where the characters are obvious to his eye, the traits are similarly obvious to his eye, the characters map to genes (locations on chromosomes) and the traits map to alleles (different versions at the locus).
if he had have picked harder characters... like the range of skin color in humans... or seed size... or human height... he would have had a harder time of things. because there isn't a single gene or a particular allele that controls that. it is messier.
for mental illness...
what are the 'characters'?
sometimes characters can be hard to find... morgan bred fruit flies (oh god i am starting to get sick of reading about freaking fruit flies) trying to find a 'character' - something that there was phenotypic variation on. he bred them for years and was getting tired of his fruit flies and then all of a sudden he got a fruit fly with white eyes instead of the usual red! so now he had a 'character' (eye color) and 'traits' (red, white). and so now he can see about getting individuals who 'breed true' (are homozygotes for the traits) and then he can see how they play in Mendellian fashion...
but what are the 'characters' for mental illness?
does the DSM provide categories of 'traits'?
conceptually confusing...
poster:alexandra_k
thread:1050240
URL: http://www.dr-bob.org/babble/20130828/msgs/1050283.html