Characterization of two children with tetrasomy 18p syndrome through multiplex ligation-dependent probe amplification and single nucleotide polymorphism-array: expanding phenotype?

Abstract

Tetrasomy 18p is characterized by intellectual disability and systemic alterations. The aim of this study is to describe two patients with tetrasomy 18p, one of them with clinical data not previously reported. Genomic DNA was analyzed by multiplex ligation-dependent probe amplification and single nucleotide polymorphism-array. The final molecular result for each of the patients was arr (hg19) 18p11.32-p11.21 (136.226-15,157.836) × 4 dn and arr (hg19) 18p11.32-p11.21 (134,878, −15,149,748) × 4 dn. The results of both parents were normal. Both patients showed data compatible with tetrasomy 18p. However, one patient presented atopic dermatitis, café-au-lait spots, and thyroglossal cysts. This data have not been reported in patients with tetrasomy 18p before.

Keywords

• Tetrasomy 18p. Multiplex ligation-dependent probe amplification. Single nucleotide polymorphism-array.