Prenatally diagnosed submicroscopic familial aberrations at 18p11.32 without phenotypic effect

Abstract

Abstract Background Recent development of MLPA (Multiplex-Ligation-dependent Probe Amplification, MRC-Holland) and microarray technology allows detection of a wide range of new submicroscopic abnormalities. Publishing new cases and case reviews associated with both clinical abnormalities and a normal phenotype is of great value. Findings/results We report on two phenotypically normal foetuses carrying a maternally-inherited interstitial submicroscopic abnormality of chromosome 18p11.32. Both abnormalities were found with the aneuploidy MLPA kit P095 during rapid aneuploidy detection, which was offered along with conventional karyotyping. Foetus 1 and its mother have a 1,7 Mb deletion and foetus 2 and its mother have a 1,9 Mb duplication. In both cases normal babies were born. We used the HumanCytoSNP-12 array of Illumina to visualize the CNVs and map the breakpoints. Conclusions We suggest that a CNV at 18p11.32 (528,050-2,337,486) may represent a new benign euchromatic variant.

Keywords

• 18p11.32 deletion
• 18p11.32 duplication
• submicroscopic abnormality
• normal phenotype
• MLPA
• SNP array