Three cases of ring chromosome 2, one derived from a paternal 2/6 translocation.

摘要: Two cases of primary ring chromosome 2 and one case a secondary to paternal 2/6 translocation are described compared with fourth from the literature. The breakpoints in two identical same as breakpoint on composite ring. three rings have number symptoms common, but other needed identify possible deletion syndrome. levels enzyme MDH-1 were within normal range Cases 1 2. Thus we localised locus for segment 2p23→p25; this had previously been p23→pter.