Allele-specific polymerase chain reaction for the detection of single nucleotide polymorphism in amlodipine-induced gingival enlargement

Abstract

What is known and objective: Studies indicate that there is an increased serum concentration of amlodipine (a calcium channel blocker used to treat hypertension and angina) in patients having mutant multidrug resistance 1 (MDR1) gene. Hence, genetic factors may play a very significant role in amlodipine-induced complications including gingival enlargement.

Case description: Three patients with amlodipine-induced gingival enlargement showed improvement following drug substitution of amlodipine with enalapril (an angiotensin-converting enzyme inhibitor) and non-invasive periodontal therapy. Using allele-specific polymerase chain reaction, single nucleotide polymorphism of MDR1 gene of heterozygous mutant type (CT genotype) was identified in all three cases.

What is new and conclusion: Drug-induced complications can potentially be a result of genetic factors, in combination with various local and systemic factors. Identifying genetic polymorphisms early might help predict adverse reactions and determine prognosis.

Keywords: MDR1; adverse effect; amlodipine; calcium channel blocker; genetic polymorphisms; gingival enlargement.