Mosaic small supernumerary marker chromosome 1 at amniocentesis: Prenatal diagnosis, molecular genetic analysis and literature review

• We present prenatal diagnosis of sSMC(1) involving 1p21.1-q11.
• The analysis was based on aCGH and FISH.
• We discuss the genotype–phenotype correlation.
• A review of prenatally detected sSMC(1) is presented.

We present prenatal diagnosis and molecular cytogenetic analysis of mosaic small supernumerary marker chromosome 1 [sSMC(1)]. We review the literature of sSMC(1) at amniocentesis and chromosome 1p21.1-p12 duplication syndrome. We discuss the genotype–phenotype correlation of the involved genes of ALX3, RBM15, NTNG1, SLC25A24, GPSM2, TBX15 and NOTCH2 in this case.