title: South Indian men with reduced CAG repeat length in the androgen receptor gene have an increased risk of prostate cancer.
abstract: The androgen receptor (AR) gene possesses polymorphic CAG tandem repeats and the repeat length has been inversely related to the risk of prostate cancer (PCa). The distinct ethnic variation in the CAG repeat length may be correlated to differences in PCa risk in different populations. To evaluate the CAG repeat length in the AR gene and the implications for PCa, we screened 87 PCa patients and 120 control subjects from South India. The mean CAG repeat length in PCa patients was significantly smaller than that of controls (17.0 vs 20.7; P < 0.001). Men with < or = 19 CAG repeats had a significantly increased risk of cancer compared to those with >19 CAG repeats (age-adjusted OR = 7.01; 95% CI = 3.52-13.94; P < 0.001). However, no significant association was observed between CAG repeats and age of onset or prostate-specific antigen levels. Although there was a trend towards shorter CAG repeat length in high grades of cancer, it was not significant (P = 0.085). Thus, our results suggest an association between short CAG repeats in the AR gene and PCa risk in South Indian men. Further, we propose that CAG repeats could be used as a prognostic marker for PCa diagnosis.
authors.affiliation: Department of Human Genetics, Sri Ramachandra Medical College and Research Institute (Deemed University), Porur, Chennai, 600116, Tamil Nadu, India.
authors.forename: Vijayalakshmi
authors.initials: V
authors.lastname: Krishnaswamy
authors.affiliation: Centre for Cellular and Molecular Biology, Hyderabad, India.
authors.forename: Thangaraj
authors.initials: T
authors.lastname: Kumarasamy
authors.affiliation: Department of Human Genetics, Sri Ramachandra Medical College and Research Institute (Deemed University), Porur, Chennai, 600116, Tamil Nadu, India.
authors.forename: Vettriselvi
authors.initials: V
authors.lastname: Venkatesan
authors.affiliation: Department of Urology and Renal Transplantation, Sri Ramachandra Medical College and Research Institute (Deemed University), Porur, Chennai, India.
authors.forename: Sunil
authors.initials: S
authors.lastname: Shroff
authors.affiliation: Department of Human Genetics, Sri Ramachandra Medical College and Research Institute (Deemed University), Porur, Chennai, 600116, Tamil Nadu, India.
authors.forename: Vikram R
authors.initials: VR
authors.lastname: Jayanth
authors.affiliation: Department of Human Genetics, Sri Ramachandra Medical College and Research Institute (Deemed University), Porur, Chennai, 600116, Tamil Nadu, India. wise_soly@yahoo.com.
authors.forename: Solomon F D
authors.initials: SFD
authors.lastname: Paul
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005006:Ethnicity; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000235:genetics*; D011944:Receptors, Androgen / Q000235:genetics*; D012307:Risk Factors; D018911:Trinucleotide Repeats
chemical_list: D011944:Receptors, Androgen