Microchimerism in twins.
BACKGROUND
The aim of this paper was to report the occurrence of peripheral blood chimerism in newborns from bigeminal pregnancies.


METHODS
Cord blood collected from 50 pairs of twins constituted the biological material studied. Analyses included: DNA isolation, quantitative and qualitative assessment of DNA preparations, hybridization analysis of SLS type as well as of MLS type, and analysis of microsatellite sequences with regard to polymorphisms using polymerase chain reaction.


RESULTS
The presence of additional fragments of DNA in peripheral blood lymphocytes was found in four out of fifty pairs of monozygotic twins (8%) at locus D7S21 (7p22, n = 3) and locus D12S11 (12q24.3, n = 1). In these cases, the presence of additional DNA fragments was also proved by analysis of microsatellite sequence polymorphisms at loci HUMPLA2A1 (pancreatic phospholipase A-2, 12q23), HUMCYARO (cytochrome P450, 15q21.1) and HUMvWF (von Willebrand factor, 12p13).


CONCLUSIONS
The results of our study confirm the occurrence of chimerism in twins and constitutes the starting point for further studies aimed at determining the clinical significance of chimerism in twins both for women and fetuses.
Department of Functional Anatomy, University School of Physical Education, Poznan, Poland.
Małgorzata
M
Waszak
Department of Functional Anatomy, University School of Physical Education, Poznan, Poland.
Krystyna
K
Cieślik
Department of Biotechnology and Molecular Biology, Institute of Natural Fibres and Medicinal Plants, Poznan, Poland.
Karolina
K
Wielgus
Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland.
Ryszard
R
Słomski
Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland.
Marlena
M
Szalata
Institute of Human Genetics, Polish Academy of Sciences, Poznan, Poland.
Marzena
M
Skrzypczak-Zielińska
Perinatology and Gynaecology Clinic, Medical University, Poznan, Poland.
Joanna
J
Kempiak
Perinatology and Gynaecology Clinic, Medical University, Poznan, Poland.
Grzegorz
G
Bręborowicz
chimerism; mosaicism; zygosity of twins