A pedigree showing the fragile site at Xq27 in a severely retarded female and in other less retarded carriers is described. Two of the four moderately retarded males with the fra(X)(q27) show macro-orchidism, and a variety of other features usually used to support the effects of the fra(X)(q27) are also inconsistent. A second fragile site at (10)(q23) is also present and in the two oldest femal...

Tandem stop mutations K26X and H27X in human immunodeficiency virus type 1 (HIV-1) vif compromise virus replication in human T-cell lines that stably express APOBEC3F (A3F) or APOBEC3G (A3G). We previously reported that partial resistance to A3G could develop in these Vif-deficient viruses through a nucleotide A200-to-T/C transversion and a vpr null mutation, but these isolates were still susce...

We report a baby with the features of Rieger syndrome and a de novo interstitial deletion of 4q which includes band 4q26 and an adjoining GTL light band, either q25 or q27. Rieger syndrome is provisionally mapped to 4q23----q27 but band 4q26 has been excluded as a possible site, suggesting that Rieger syndrome must map to a band, either 4q25 or 4q27, adjoining 4q26.