[Prenatally identified case of mosaicism of chromosome 16 trisomy].

We present the prenatally identified case of mosaicism of chromosome 16 trisomy. A patient with the pregnancy complicated in the first trimester by the threat of breaking was refered to the high risk group according to the results of the screening program. The ultrasonic research revealed a number of phenotypical pathologies in 19-weeks-old fetus such as congenital heart disease (ventricular septal defect), hyperechoic bowel, single umbilical artery and some other ones. Cytogenetical and FISH analyses of the placental villi revealed karyotype with chromosome 16 trisomy. The further research of amniotic fluid cells revealed the karyotype of fetus as mos47,XX,+16 / 46,XX. The pathologoanatomic research of the abortus has verified the multiple congenital malformations.

[The role of ultrasonic and cytogenetic markers in prenatal diagnostics].

As a result of leadthrough 288 invasive manipulations with the use of cytogenetic and molecular-cytogenetic methods we have found 16 different disorders in the fetus karyotype of the expectant mothers of high risk groups. For the most part the Down syndrome and the Shereshevsky-Therner syndrome were detected among aneuploidies. The maximal amount of anomalous karyotypes (28.6%) was detected at the pregnants with congenital malformations in the fetus. The proofs of the increased frequencies of some chromosome homologue heteromorphisms were got in the group of patients where the so-called "soft markers" of aneuploidies or their combination with biochemical markers were used as supposition for the invasive procedure. The echographic screening proved to be the most informative method among the different approaches to the formation of the groups of the high genetic risk.