USMLE Forum - Largest USMLE Community

A pregnant woman with a family history of fragile X
syndrome wants prenatal diagnosis of her fetus. Amplifica-
tion of the appropriate region of the FMRI gene by PCR is
attempted on DNA from amniotic fluid cells, but no ampli-
fied products are obtained. What is the best next step?
A Routine karyotype of the amniotic fluid cells
B Routine karyotype of the unaffected father
C Southern blot of the DNA from the anmiotic fluid
cells
D PCR analysis of the mother's FMR1 gene
E No further tests necessary

e????

e????

southern blot of the dna ie ,C

southern blot of the dna ie ,C

southern blot of the dna ie ,C

southern blot of the dna ie ,C

EEEE

EEEE

ee