Telomeric length varies with age and polymorphisms of the MAOA gene promoter in peripheral blood cells obtained from a community in Taiwan.

Objective: Telomere shortening and increased MAOA gene activity both occur with aging. We undertook to develop a predictive model of telomere shortening and to investigate the possible association between MAOA gene promoter polymorphisms and telomere length as influenced by age and gender.

Methods: A stratified random household sample was selected from a community in southern Taiwan. Of 1231 subjects attending our health-screening program, 441 agreed to have additional venous blood withdrawn for DNA extraction and genetic study. Exactly 433 subjects completed the questionnaires and genetic analysis. Their telomere lengths were distributed (6.4-11.63 kb).

Results: The rate of shortening per year was 69 base pairs, and the gender difference in length was not statistically significant (F = 0.091, P = 0.763). The lognormal distribution of telomere lengths was linear. The polynomial regression analysis showed Ln (telomere length) = -2.57-0.007 x age - 0.34 MAOA (adjusted R-square = 0.60). The gender effect on telomere length was not statistically significant (P = 0.52). No interaction effects were found between age, gender and MAOA gene polymorphisms. The high-activity allele of the MAOA promoter polymorphisms were negatively associated with telomere length (P = 0.013). Structural equation modeling confirmed the null model structure. The present data suggest that high-activity MAOA promoter gene polymorphisms, as in aging, are a risk factor for telomeric shortening.

Conclusions: Central nervous system serotonergic activity correlates with human aggressive behavior and depression in many studies, and the MAOA promoter gene may also serve as a clinical marker in the treatment of cardiovascular disease. The predictive model and table of telomere length presented in this study will provide a quick reference for future studies.