Genetic polymorphisms and human reproduction: a study of phosphoglucomutase in spontaneous abortion

Theoretical arguments suggest that variation of metabolic parameters due to genetically determined enzyme polymorphisms may exert important effects on implantation and zygote development. The polymorphic enzyme phosphoglucomutase controlled by locus 1 (PGM1) is a phosphotransferase which plays a key role in carbohydrate metabolism and it is present in high concentrations in placental tissue. The enzyme has been studied in 47 couples with habitual abortion, in 36 women with single episodes of spontaneous abortion, in 48 women with induced abortion, and in control samples of normal individuals from the same population. Among couples with habitual abortion a significant increase of mean survival time of fetuses was observed in PGM1-heterozygote mothers as compared to homozygotes. An increased proportion of couples which may produce the hypothetical PGM1-null phenotype was also observed in habitual abortion, which suggests that homozygosity for PGM10 allele may contribute to fetal loss. Investigations on polymorphic enzymes involved in placental and fetal metabolism may contribute significantly to the problem of genetic etiology of spontaneous abortion.