MAO-A and COMT genotypes as possible regulators of perinatal serotonergic symptoms after in utero exposure to SSRIs

Intrauterine exposure to SSRIs in late pregnancy can cause various serotonergic symptoms in the newborns. We associated the severity of these symptoms to neurotransmitter concentrations and genetic polymorphisms in the cytochrome P450, MAO-A and COMT enzymes. Altogether 20 children with prenatal exposure to citalopram or fluoxetine were genotyped. Infants with two high-activity alleles of the MAO-A gene had significantly higher serotonergic symptom scores than infants with at least one low-activity allele (mean 8.8 vs. 2.4, p = 0.024). These infants had also higher cord blood DHPG concentrations (p = 0.0054). Carriers of the high-activity COMT alleles had higher cord blood prolactin concentrations (p = 0.044). According to our results, the higher serotonergic symptom score and cord blood DHPG concentration in rapid MAO-A metabolizers suggest that norepinephrine may modify the severity of perinatal serotonergic symptoms. The COMT 1947G > A polymorphism may affect the occurrence of respiratory distress symptoms in infants with prenatal SSRI-exposure via a mechanism involving prolactin.