A small supernumerary marker chromosome present in a Turner syndrome patient not derived from X- or Y-chromosome: A case report

Abstract

Background. Small supernumerary marker chromosomes (sSMC) can be present in numerically abnormal karyotypes like in a 'Turner-syndrome karyotype' mos 45,X/46,X,+mar. Results. Here we report the first case of an sSMC found in Turner syndrome karyotypes (sSMCT) derived from chromosome 14 in a Turner syndrome patient. According to cytogenetic and molecular cytogenetic characterization the karyotype was 46,X,+del(14)(q11.1). The present case is the third Turner syndrome case with an sSMCT not derived from the X- or the Y-chromosome. Conclusion. More comprehensive characterization of such sSMCT might identify them to be more frequent than only ∼0.6% in Turner syndrome cases according to available data. © 2009 Sheth et al.