Quantitative evaluation of collagen type VI and SOD gene expression in the nuchal skin of human fetuses with trisomy 21.
OBJECTIVE
To investigate the involvement of the genes encoding for COL6A1, COLA2 and super-oxide dismutase (SOD) in the mechanism for the retention of subcutaneous fluid in fetuses with trisomy 21.


METHODS
During a 7-month period (November 2004-May 2005), human fetal skin from the nuchal region was obtained from euploid fetuses and from fetuses with trisomy 21 following abortions and terminations of pregnancy. Cell cultures were performed from nuchal skin. Quantification of COL6A1, COL6A2, COL6A3 and SOD mRNAs were performed using real-time quantitative RT-PCR.


RESULTS
Twelve fetuses were studied between 13-15 and 19-20 weeks of gestation including 7 cases of trisomy 21. A significant overexpression of genes of interest was demonstrated in trisomy 21 fetuses when compared with euploid fetuses, in the first and in the second trimester of pregnancy (p < 0.0001).


CONCLUSIONS
This study demonstrates a homogeneous overexpression of the genes encoding for alpha1 and alpha2 chains of Collagen type VI, and SOD in nuchal skin of human trisomy 21 fetuses. Persistence of this overexpression in the second trimester of pregnancy, despite the absence of an enlarged nuchal translucency (NT), may characterize some compensatory mechanisms.
Quarello
Edwin
E
Department of Obstetrics and Gynecology, CHI Poissy St Germain, Université Paris-Ouest, Poissy, France. e.quarello@wanadoo.fr
Guimiot
Fabien
F
Moalic
Jean-Marie
JM
Simoneau
Michel
M
Ville
Yves
Y
Delezoide
Anne-Lise
AL
D024142:Collagen Type VI / Q000235:genetics*; D004314:Down Syndrome / Q000000981:diagnostic imaging / Q000235:genetics*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D005865:Gestational Age; D006801:Humans; D048208:Nuchal Translucency Measurement; D011247:Pregnancy; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000737:chemistry; D013482:Superoxide Dismutase / Q000235:genetics*
D024142:Collagen Type VI; D012333:RNA, Messenger; D013482:Superoxide Dismutase