Molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome derived from chromosome 8 associated with congenital hypoplasia of the tongue and review of the literature

OBJECTIVE: To present molecular cytogenetic characterization of mosaic supernumerary ring chromosome 8 which has trisomy of a region of chromosome 8p12-q21.13 associated with congenital hypoplasia of the tongue and review of the literature. CASE REPORT: A 27 year-old woman presented with congenital hypoplasia of the tongue. The chromosome karyotype of peripheral blood lymphocytes was detected by conventional cytogenetic analysis. The genome copy number variations were detected by SNP array. Conventional cytogenetic analysis of the peripheral blood revealed a karyotype of 47,XX,+mar[60]/46,XX[40]. SNP array revealed that there was a duplication of 45.2 Mb at arr[hg19] 8p12q21.13(36,013,636-81,263,140) × 2-3. CONCLUSION: With this study a patient involving mosaic trisomy 8p12-q21.13 along with clinical properties, is described and compared to previously reported cases involving a small supernumerary marker chromosome (sSMC) derived from chromosome 8.