CONTEXT: Advancing age is accompanied by accumulation of ill-health and shortening of chromosomal telomeres signifying biological ageing. @entity251 (T) is metabolised to @entity586 ( @entity587 ) by 5 ga-reductase ( @entity35006 ) and to @entity53 (E2) by aromatase ( @entity4819 ). Telomerase preserves telomeres, and T and E2 regulate telomerase expression and activity in vitro. OBJECTIVES: To establish whether circulating T or its metabolites @entity587 or E2, and single nucleotide polymorphisms (SNPS) in @entity35006 or @entity4819 associate with leucocyte telomere length (LTL) in @entity1 . @entity1 AND METHODS: Early morning serum T, @entity587 and E2 were assayed using mass spectrometry, and @entity35006 and @entity4819 snps and LTL analysed by PCR in 980 @entity1 from the Western Australian Busselton Health Survey. LTL was expressed as the T/S ratio. RESULTS: @entity1 were aged (mean  SD) 53.7  15.6 years. LTL decreased linearly with age, from T/S ratio 1.89  0.41 at <30 years to 1.50  0.49 at 70 to <80 years (r=-0.225, p<0.0001). After adjustment for age, @entity587 and E2 were positively correlated with LTL ( @entity587 r=0.069, p=0.030; E2 r=0.068, p=0.034). The @entity35006 @entity69001 polymorphism was associated with serum @entity587 but not with LTL. Three dominant alleles of @entity4819 were each associated with lower serum E2 and shorter LTL: @entity19113 T (E2 59.3 vs 68.6 pmol/L, p<0.0001; T/S ratio 1.54 vs 1.62, p=0.045), @entity69002 C (60.5 vs 68.1 pmol/L, p=0.0005, 1.54 vs 1.62, p=0.035) and @entity39449 A (59.9 vs 68.9 pmol/L, p<0.0001, 1.54 vs 1.63, p=0.020). A single copy haplotype C/T/I/A/T @entity69002 / @entity19113 / @entity69003 / @entity39449 / @entity69004 (52% prevalence) was associated with both lower E2 and shorter LTL. CONCLUSIONS: In men, serum @entity587 and E2 correlate with LTL independently of age. Aromatase gene polymorphisms include 3 dominant alleles which are associated with both lower serum E2 and shorter LTL. E2 influences telomere length in vivo thus warranting further studies to examine whether hormonal interventions might slow biological ageing in @entity1 .

Epidemiological and Mendelian randomisation studies of @entity586 and @entity53 , and leucocyte telomere length in XXXX .

@entity1 :: ('9606', 'Species') :: ['men', 'Men', 'PARTICIPANTS'] @entity35006 :: ('6716', 'Gene') :: ['SRD5A2'] @entity251 :: ('MESH:D013739', 'Chemical') :: ['Testosterone'] @entity69003 :: ('rs11575899', 'SNP') :: ['rs11575899'] @entity586 :: ('MESH:D013196', 'Chemical') :: ['dihydrotestosterone'] @entity4819 :: ('1588', 'Gene') :: ['CYP19A1'] @entity69001 :: ('rs9282858', 'SNP') :: ['rs9282858'] @entity19113 :: ('rs2899470', 'SNP') :: ['rs2899470'] @entity69002 :: ('rs10046', 'SNP') :: ['rs10046'] @entity53 :: ('MESH:D004958', 'Chemical') :: ['estradiol'] @entity69004 :: ('rs17703883', 'SNP') :: ['rs17703883'] @entity587 :: ('CHEBI:16330', 'Chemical') :: ['DHT'] @entity39449 :: ('rs700518', 'SNP') :: ['rs700518']
@entity1 :: (9606,Species) :: ['men']
