Brief clinical report - Recurrent involvement of chromosomal region 6q21 in heterotaxy

We present a patient with heterotaxy and a de novo, apparently balanced rec iprocal translocation with breakpoints at 6q21 and 20p13. Another patient w ith heterotaxy was previously reported with a de novo balanced translocatio n involving chromosome band 6q2l. The breakpoints in both patients on 6q2l were found to be located in the same chromosomal region spanning maximally 2 Mb. We speculate that the two breakpoints lead to the disruption of the f unction of a single gene, either directly or through long distance effects. Alternatively, the present observation suggests additional heterogeneity i n heterotaxy in humans. (C) 2001 Wiley-Liss, Inc.