[Case reports of patients with a marker chromosome].

Small, usually supernumerary chromosomes, denoted as marker chromosomes or markers, can be represented by various phenotypic expression, that depends on their origin and extent. Our article presents results of molecular cytogenetic analysis (FISH) of 34 patients with identified marker chromosome. In 21 cases a marker derived from acrocentric chromosome was identified, in 9 cases markers of gonosomal origin [der(X), der(Y)], and in 4 patients markers of some other chromosomes (5, 17, 18) were proved.

[Paracentric inversions of human chromosomes and their risks].

The incidence of paracentric inversions in the general population has not been clearly established, it ranges from 0.09 to 0.49/1,000.

Currarino triad: concurrent US and MRI diagnosis in the fetus and the mother.

We report an unusual case of the complete Currarino triad diagnosed in a fetus at 21 weeks' gestation by means of prenatal ultrasonography (US). The highly suspicious findings in the fetus were accompanied by analogous US findings in the mother who suffered from mild symptoms of up to that time unrecognized Currarino triad. Consecutively, magnetic resonance imaging (MRI) confirmed the findings simultaneously in the fetus and in her mother.

[Prenatal diagnosis of de novo complex balanced rearrangements in chromosomes 3,4, and 13] ].

A case of apparently balanced de novo complex chromosome rearrangement with three breaks found in foetus by amniotic fluid examination is described. Amniocentesis was indicated because of low AFP in maternal serum during the first pregnancy of 25-year-old healthy woman. Her family anamnesis as well as her husbands on was insignificant, chromosomes were normal.

[Pericentric inversion of human chromosomes and its risks] ].

Pericentric inversions of human chromosomes represent rearrangements are formed between two breaks on the short and on long arms of the chromosome with following rotation and new connection of the separated segment in the reversed position. The abnormality does not result in most of the carriers to any clinical manifestations. However, the basic risk the carriers of such inversion are exposed is the possibility of formation of a recombinant aneusomy--later transformation of the inverted chromosome during gametogenesis.