|
Genetics... Q 2 - psychmledr
|
09-30-2010, 07:44 PM
Symptoms of this disease include a history of developmental regression, mental retardation, and characteristic hand movement in affected females.
A. Huntington disease B. Rett syndrome C. Duhenne muscular dystrophy D. Sickle cell disease E. Fragile X syndrome
09-30-2010, 07:47 PM
BBBBBBBBBBBBBBB
Xlinked dominant , xpressed only in females D/D childhood disintegrative disorder
10-01-2010, 05:44 AM
B.
Rhett syndrome is generally lethal in males, and is characterized by mental retardation and characteristic hand movements in affected females, among other findings. Mental retardation is associated with Fragile X syndrome, but inheritance is autosomal recessive and mostly males are affected. Mental retardation is not associated with Huntington disease, duchenne muscular dystrophy, or sickle cell disease.
10-01-2010, 07:27 AM
Isnt Fragile X syndrome an X linked dominant ds which can also present in females
10-01-2010, 09:46 AM
Yes, it is X-linked dominant. Because males normally have only one copy of the X chromosome, those males with significant trinucleotide expansion at the FMR1 locus are symptomatic. They are intellectually disabled and may show various physical features of the fragile X syndrome.
Females have two X chromosomes and thus have an increased probability of having a working FMR1 allele. Females carrying one X chromosome with an expanded FMR1 gene can have some signs and symptoms of the disorder or be normal. |
| « Next Oldest | Next Newest » |
