RESUMO
Background: To verify the hypothesis that the incidence of chromosomal abnormalities increases in babies conceived by different assisted reproduction procedures. The availability of the umbilical cord blood encouraged us to study this hypothesis via this method
Materials and Methods: This is a descriptive study, umbilical cord blood samples of assisted reproductive technology [ART] children were analyzed with standard cytogenetic techniques [G banding]. Karyotyping was possible in 109 cases
Results: The number of abnormal cases was four [3.7%], among which, three cases [2.8%] were inherited and only 1 case [0.9%] was a de novo translocation. In total, the incidence of de novo chromosomal abnormalities was in the range observed in all live births in the general population [0.7-1%]
Conclusion: No significant difference in the incidence of chromosomal abnormality was found between ART and naturally conceived babies. To date, several studies have examined the medical and developmental outcome of ART children and still have not reached a definite conclusion. Genetic counseling is recommended as an integral part of planning of treatment strategies for couples wishing to undergo ART
RESUMO
Embryonic germ [EG] cells are the results of reprogramming primordial germ cells [PGC] in vitro. Studying these cells can be of benefit in determining the mechanism by which specialized cells acquire pluripotency. Therefore in the current study we have tried to derive rat EG cells with inhibition of transforming growth factor-beta [TGFbeta] and mitogen-activated protein kinase kinase [MEK] signaling pathways. In this experimental study, rat PGCs were cultured under feeder free condition with two small molecules that inhibited the above mentioned pathways. Under this condition only two-day presence of stem cell factor [SCF] as a survival factor was applied for PGC reprogramming. Pluripotency of the resultant EG cells were further confirmed by immunofluorescent staining, directed differentiation ability to neural and cardiac cells, and their contribution to teratoma formation as well. Moreover, chromosomal stability of two different EG cells were assessed through G-banding technique. Formerly, derivation of rat EG cells were observed solely in the presence of glycogen synthase kinase-3 [GSK3beta] and MEK pathway inhibitors. Due to some drawbacks of inhibiting GSK3beta molecules such as increases in chromosomal aberrations, in the present study we have attempted to assess a feeder-free protocol that derives EG cells by the simultaneous suppression of TGFbeta signaling and the MEK pathway. We have shown that rat EG cells could be generated in the presence of two inhibitors that suppressed the above mentioned pathways. Of note, inhibition of TGFbeta instead of GSK3beta significantly maintained chromosomal integrity. The resultant EG cells demonstrated the hallmarks of pluripotency in protein expression level and also showed in vivo and in vitro differentiation capacities. Rat EG cells with higher karyotype stability establish from PGCs by inhibiting TGFbeta and MEK signaling pathways