No mitochondrial DNA deletions but more D-loop point mutations in repeated pregnancy loss.
OBJECTIVE
repeated pregnancy loss (RPL) occurs in 1 out of 300 couples, and the cause of about 50% of them remains idiopathic. Mitochondria have an important role in human development through ATP production and their involvement in apoptosis.


METHODS
96 RPL and 96 control females were used to investigate the frequency of deletions and point mutations in the displacement loop (D-loop) on mitochondria. Multiplex PCR and DNA sequencing methods were used to detect possible variations in the mitochondrial DNA (mtDNA).


RESULTS
no deletions but a high frequency of point mutations were found in RPL females; among 129 variations observed in RPL, 22 mutations were significant (P < 0.05) and the insertion of C in nucleotide 114 was novel.


CONCLUSIONS
high rate of mutations in D-loop of mtDNA was observed in maternal blood, a fact that may have a direct or indirect role in inducing RPL. The results can be used in the assessment of RPL and designing possible treatments for improving assisted reproduction.
Seyedhassani
Seyed Mohammad
SM
National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
Houshmand
Massoud
M
Kalantar
Seyed Mehdi
SM
Modabber
Glayol
G
Aflatoonian
Abbas
A
D000026:Abortion, Habitual / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000737:chemistry*; D005260:Female; D006801:Humans; D017354:Point Mutation; D011247:Pregnancy; D017422:Sequence Analysis, DNA
D004272:DNA, Mitochondrial