Jj. Mitchell et al., U-TYPE EXCHANGE IN A PARACENTRIC INVERSION AS A POSSIBLE MECHANISM OFORIGIN OF AN INVERTED TANDEM DUPLICATION OF CHROMOSOME-8, American journal of medical genetics, 49(4), 1994, pp. 384-387
A mentally retarded male with dysmorphic features was found to have a
de novo 46,XY,inv dup(8) (p.23.1-->12). Confirmation of the segments d
uplicated in the rearrangement was achieved by biochemical analysis of
glutathione reductase, which maps to 8p21.1, and DNA studies using th
e chromosome specific probe y-19-1D (D85131), which maps to 8p21. Assa
y of cathepsin B, which has been localised to 8p22, did not differ fro
m controls with normal chromosomal constitution. DNA studies using the
Defensin 1 gene probe, which maps to 8p23, showed a previously undete
cted deletion of that segment. We propose that the inverted tandem dup
lication/deletion arose as a single U-type exchange within an inversio
n loop. (C) 1994 Wiley-Liss, Inc.