Karyotyping of Lymphocytes and Epithelial Cells of Distinct Embryonic Origin Does Not Help to Predict the Turner Syndrome Features.

Background: In Turner syndrome (TS), fluorescent in situ hybridization (FISH) karyotyping offers an alternative to classical karyotyping.

Objective: We tested the added value of FISH karyotyping from lymphocytes (mesodermal origin), buccal cells (ectodermal origin), and a rear-tongue smear (endodermal origin) to determine the 45,X cell line fraction and its impact on patient phenotype.

Design And Patients: Classical karyotyping and three FISH assays were done in 153 girls and women previously diagnosed with TS in four university hospitals.

Haplotype analysis of the X chromosome in patients with Turner syndrome in order to verify the possible effect of imprinting on selected symptoms.

Aims: Turner syndrome is the only chromosome monosomy that is postnatally compatible with life. The reported incidence of TS is 1 in 2500 liveborn girls. The phenotype of these girls is highly variable, with cardiac abnormalities being life-threatening defects.

Partial trisomy and tetrasomy of chromosome 21 without Down Syndrome phenotype and short overview of genotype-phenotype correlation. A case report.

Aims: Trisomy of chromosome 21 is associated with Down syndrome (DS) - the commonest genetic cause of mental retardation. We report two unusual cases with partial trisomy of chromosome 21 and tetrasomy of chromosome 21 without DS phenotype. We include a short overview of the genotype-phenotype correlation studies in discussion.

Refined fluorescent STR quantification of cell-free fetal DNA during pregnancy in physiological and Down syndrome fetuses.

Background: Cell-free fetal (cff) DNA analysis by short tandem repeats (STR) has the advantage of better recognizing the different genotypes. However, quantitative examination by quantitative fluorescent (QF) polymerase chain reaction (PCR) by STRs is limited to only a rough approximation. This project focuses on a more precise calculation of the relative cff DNA amount tested in the STRs' loci.