Diagnostic yield by supplementing prenatal metaphase karyotyping with MLPA for microdeletion syndromes and subtelomere imbalances.

[wolf-hirschhorn syndrome]

The aim of the study was to retrospectively assess the relevance of using multiplex ligation-dependent probe amplification (MLPA ) for detection of selected microdeletion syndromes (22 q 11 , Prader-Willi /Angelman , Miller-Dieker , Smith-Magenis , 1 p -, Williams ), the reciprocal microduplication syndromes and imbalance at the subtelomere regions of chromosomes in a routine prenatal setting .A total of 530 prenatal samples were analysed by commercial MLPA kits (SALSA P 064 , P 036 and P 069 ) in addition to rapid aneuploidy testing and G-band karyotyping .Among the prenatal samples with a normal metaphase karyotype , nine submicroscopic imbalances were detected : seven 22 q 11 deletions (Velocardiofacial /DiGeorge syndrome ), one 15 q 11 deletion (Prader-Willi syndrome ) and one terminal deletion of the short arm of chromosome 4 (Wolf-Hirschhorn syndrome ). All imbalances were found in amniocentesis (AC ) taken due to fetal structural malformation and /or other ultrasound scan (US ) detected abnormality . The diagnostic yield was 4 .1 % in the subgroup with structural malformation and 1 .6 % in the subgroup with other US abnormality .The data set substantiates that additional MLPA analyses for selected microdeletions and subtelomere imbalances are valuable in routine prenatal diagnostics , when a malformation (s ) and /or other abnormalities are detected by US . In contrast , the additional MLPA analyses gave no diagnostic yield in case of increased nuchal translucency (NT ).

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wolf-hirschhorn syndrome

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