Smoking and human reproduction: the effect of adenylate kinase genetic polymorphism.

We investigated the possible influence of adenylate kinase genetic variability on the effect of maternal smoking on intrauterine selection and development. Adenylate kinase locus 1 belongs to a family of monophosphate kinases that plays an important role in the synthesis of nucleotides involved in several metabolic functions. Three hundred forty-five newborn consecutive infants from the Caucasian population of Rome and 360 consecutive infants from the Caucasian population of Penne were studied. The proportion of newborns carrying AK1*2 allele was analyzed in relation to smoking and maternal age. The effect of smoking on birth weight was also analyzed in relation to AK1 phenotype and maternal age. Statistical analyses have been performed according to SPSS programs. In offspring of women aged 28 years or less, the proportion of newborns carrying the AK1*2 allele is much higher in smoking than in nonsmoking mothers (13.2% versus 2.6%). Such association is lacking in mothers aged more than 28 years (6.5% versus 9.2%). The negative effects of smoke on birth weight is more marked in AK11 mothers than in AK1*2 carriers. The data suggest that zygotes carrying AK1*2 allele are relatively protected from the damaging effects of smoking, resulting in a relatively higher proportion of newborns carrying this allele among smoking mothers.