Facteurs génétiques déterminant les variations anatomiques de la prostate Genetic determinants of anatomical variants of the prostate

SummaryIntroduction.„ The determinants of macroscopic and microscopic anatomical variants of theprostate during ageing are poorly de“ned. The authors evaluated the correlation between spe-ci“c gene polymorphisms involved in androgen and oestrogen synthesis and gross (prostaticweight) and microscopic anatomy (stroma/epithelium ratio) of the prostate during ageing.Methods.„ The prostatic weight and stromal surface area of an autopsy series of 85 men overthe age of 50 were measured, then compared as a function of gene polymorphisms involvedin androgen or oestrogen regulation. The following polymorphisms were studied: number ofCAG repeats of the androgen receptor (AR), number of TA repeats and theV89Lvariant of the5-alpha-reductase gene (SRD5A2) for androgens, and the A1A2 variant of 17-alpha-hydroxylase(CYP17) and number of TTTA repeats of the aromatase (CYP19) for oestrogens.Results.„ No correlation was observed between the number of TA repeats of theSRD5A2geneor TTTA repeats of theCYP19gene and anatomical parameters of the prostate. A statisticallysigni“cantpositivecorrelationwasobservedbetweenageandprostateweight(r=0.21, p=0.05)and a statistically signi“cant negative correlation was observed between prostate weight andnumber of CAG repeats (r=Š 0.32, p=0.003). The group with less than 20 CAG repeats wasassociated with a higher prostate weight than the other group. The stromal surface area wasgreater in the [20„23] CAG repeat group (p=0.02), and in the A2A2 group ofCYP17(p=0.016)than in the other groups.Conclusion.„ A small number of CAG repeats is associated with a higher prostate weight. Themean number of CAG repeats of the androgen receptor and the A2A2 variant of theCYP17geneare associated with a larger stromal surface area.© 2008 Elsevier Masson SAS. Tous droits reserves.