Array Characterization of Prenatally Diagnosed 15q26 Microdeletion and 2q37.1 Duplication: Report of a New Case with Multicystic Kidneys

We report on a molecular cytogenetic characterization of 15q26 deletion and 2q37.1
duplication in a fetus presenting with intrauterine growth restriction (IUGR), diaphragmatic
hernia, multicystic kidneys, left kidney pyelectasis, and clubfeet. A terminal
15q26 deletion and a terminal 2q duplication of at least 10 and 9 Mb, respectively,
derived from a maternal translocation, was found. The 15q26 deletion represents a
contiguous gene deletion syndrome mainly characterized by IUGR, congenital diaphragmatic
hernia, and less frequently kidney defects. This deletion encompasses the
IGF1R and COUPTF2 genes, known to lead to fetal growth retardation syndrome.
However, kidney malformations are less well known in such conditions, and to the best
of our knowledge, no candidate gene has been proposed to date. Here, we review the
literature of the 15q26 deletion syndrome and suggest that hypoplastic andmulticystic
kidneys, the most commonly observed anomalies in this condition, should be
considered in the prenatal diagnosis setting. Based on COUPTF2 protein function,
we hypothesize that its haploinsufficiency might be responsible for the renal
pathology.