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Fragile X Syndrome Dominant or Recessive!

9K views 7 replies 7 participants last post by  masterji 
#1 ·
Is fragile X syndrome dominant or recessive?
FA says its recessive, Goljan too, but Kaplan says its x-linked dominant, which one should I trust now?
I'm confused, can you help me?
 
#7 ·
Fragile X syndrome has traditionally been considered an X-linked dominant condition with variable expressivity and possibly reduced penetrance. However, due to genetic anticipation and X-inactivation in females, the inheritance of Fragile X syndrome does not follow the usual pattern of X-linked dominant inheritance and some scholars have suggested discontinuing labeling X-linked disorders as dominant or recessive. Females with full FMR1 mutations may have a milder phenotype than males due to mosaicism resulting from X-inactivation. - wikipedia
 
#8 ·
you guys, criterion for differentiating recessive or dominant depends on what perspective you cling to...
usually, medical communities differentiate genetic diseased from PHENOTYPICAL EXPRESSION.
however, geneticists or biochemists use GENOTYPIC OR PROTEIN EXPRESSION as criteria.

it is just like physicists are interested in WORK and chemists are interested in ENERGY and they speak slightly altered languages even though they are trying to explain the same thing (eg. thermodynamics, quantum physics or chemistry)

honestly, IMO, memorizing genetic dz. whether they are AD or AR are mostly waste of time. but they are tested on the exam so we have no choice.
 
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