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Maria Iachina

Publications and source records attributed to Maria Iachina.

5 recordsLinked to original sources
PubMed2006

Candidate gene polymorphisms in the serotonergic pathway: influence on depression symptomatology in an elderly population.

BACKGROUND: Depressed mood is a major concern in the elderly, with consequences for morbidity and mortality. Previous studies have demonstrated that genetic factors in depression and subsyndromal depressive symptoms are no less important in the elderly than during other life stages. Variations in genes included in the serotonin system have been suggested as risk factors for various psychiatric disorders but may also serve as candidates for normal variations in mood. METHODS: This study included 684 elderly Danish twins to investigate the influence of 11 polymorphisms in 7 serotonin system genes on the mean level of depression symptomatology assessed over several years, reflecting individuals' underlying mood level. RESULTS: A suggestive association of sequence variations in genes responsible for the synthesis (TPH), recognition (5-HTR2A), and degradation (MAOA) of serotonin with depression symptomatology was found, although the effect was generally restricted to men. We also found that a specific haplotype in VMAT2, the gene encoding the vesicular monoamine transporter, was significantly associated with depression symptoms in men (p= .007). CONCLUSIONS: These results suggest that variations in genes encoding the components of serotonin metabolism may influence the basic mood level and that different genetic factors may apply in men and women.

Affect↗
PubMed2005

Hair loss among elderly men: etiology and impact on perceived age.

BACKGROUND: Androgenetic alopecia is the most common type of hair loss in men, but little is known about the etiology of androgenetic alopecia in elderly men and its impact on perceived age. Here we used a population-based twin study of men aged 70+ to assess the magnitude of the genetic component affecting hair loss and to examine the association between baldness and perceived age. METHODS: In the fourth wave of The Longitudinal Study of Aging Danish Twins we obtained digital photos of the face and photos of the vertex area of 739 elderly male twins, including 148 intact twin pairs. The degree of baldness and perceived age were assessed in each twin by five and nine nurses, respectively. The heritability of balding was estimated using structural-equation analysis, and it was tested whether baldness was associated with estimations of age. RESULTS: The intrapair correlation of degree of balding was consistently higher for monozygotic than for dizygotic twin pairs regardless of the baldness categorization used, and structural-equation analysis revealed a heritability of 79% (95% confidence interval, 0.40--0.85) for the mean baldness index. The remaining variation could be attributed to non-shared environmental effects. There was only a very weak and statistically nonsignificant association between baldness and overestimation of age. CONCLUSIONS: The majority of the variation in baldness in elderly men can be explained by genetic factors, and hair quantity has little impact on perceived age in elderly men.

Aged↗
PubMed2002

Analysis of functional abilities for elderly Danish twins using GEE models.

In this work we present a new method for genetic analysis of twin data which is based on generalized estimating equations and allows for analysis of various response types (e.g., continuous, binary, counts) combined with estimation of residual correlations. The new approach allows for control of covariates of any kind (e.g., continuous, counts) by modeling the dependence of mean and variance on background variables. The proposed method was applied to identify the covariates that have a significant influence on elderly people's functional abilities, and find the estimates for the correlation coefficients of residuals for MZ and DZ twins in a sample of 2401 Danish twin 75 years of age or older. The bootstrap method was used to obtain standard errors for correlation coefficients. It was shown, that the chosen covariates have similar effects on MZ and DZ twins, and that the residual correlation in MZ twins is significantly higher than in DZ twins, which indicates that genetic factors play an etiological role in the determination of physical status of elderly people, controlled for 10 background variables.

Activities of Daily Living↗