Recurrent miscarriage is associated with the dopamine receptor (DRD2) genotype

Area of Science:

• Genetics
• Reproductive Medicine
• Endocrinology

Background:

• Recurrent miscarriage (RM) affects a significant number of women, with underlying causes often remaining unclear.
• Dopamine receptor D2 (DRD2) plays a role in hormonal regulation, including prolactin, which is crucial for reproduction.
• Genetic variations in the DRD2 gene may influence reproductive outcomes.

Purpose of the Study:

• To investigate the association between dopamine receptor D2 (DRD2) gene polymorphisms and recurrent miscarriage (RM).
• To compare the frequency of specific DRD2 polymorphisms (rs6275 and rs6277) in women with RM versus healthy controls.
• To explore the relationship between DRD2 genotypes, serum prolactin levels, and RM.

Main Methods:

• A case-control study involving 54 women (RM patients and healthy controls).
• DNA extraction from peripheral blood for genetic analysis.
• Polymerase chain reaction (PCR) and sequencing to identify single-strand polymorphisms in the DRD2 gene (rs6275 and rs6277).
• Measurement of serum prolactin levels in all participants.

Main Results:

• The frequency of the DRD2 polymorphism 2 (rs6277) was significantly higher in women with recurrent miscarriage.
• An odds ratio of 2.37 indicated an increased risk of RM associated with the DRD2 rs6277 polymorphism.
• Women with RM exhibited higher mean serum prolactin levels (12.5 ng/ml) compared to healthy controls (8.1 ng/ml; p=0.03).

Conclusions:

• Excess homozygosity for the DRD2 rs6277 polymorphism suggests a potential genetic predisposition to recurrent miscarriage.
• This genetic variation may contribute to mild elevations in serum prolactin, potentially affecting reproductive regulation.
• The DRD2 polymorphism could play a critical role in early pregnancy implantation and maintenance.