Analysis of genetic polymorphisms of steroid 5alpha-reductase type 1 and 2 genes in Korean men with androgenetic alopecia.
BACKGROUND
Genetic polymorphisms of steroid 5alpha-reductase have been studied in androgenetic alopecia in Caucasians, but the genes encoding the two isoenzymes were not associated with male pattern baldness. Genetic polymorphisms and ethnic variations have not been studied for Asians, although it is suggested that racial difference could exist and influence clinical phenotypes.


OBJECTIVE
The purpose of our study is to investigate the genetic polymorphisms of steroid 5alpha-reductase type 1 and 2 (SRD5A1 and SRD5A2) genes in Korean population, and to study the association of these polymorphisms with the development, clinical types (female or male pattern) and therapeutic response of androgenetic alopecia.


METHODS
Sixty-six patients with androgenetic alopecia and controls consisted of 92 healthy men were included. Twenty-four patients were treated with finasteride for at least 6 months, and clinical responses were assessed by a simple classification. For type 1 isoenzyme, HinfI and NspI restriction fragment length polymorphisms (RFLPs) were detected using polymerase chain reaction method. For type 2 isoenzyme, RsaI RFLPs detected valine/leucine polymorphisms at codon 89, and MowI RFLPs detected alanine/threonine polymorphisms at codon 49.


RESULTS
We could not find any significant associations of the genetic polymorphisms of these two isoenzyme genes with androgenetic alopecia in Koreans (P>0.05). These polymorphisms were not associated with the clinical types of baldness or the response to finasteride (P>0.05).


CONCLUSIONS
These results suggest that polymorphisms of SRD5A1 and SRD5A2 genes may not be directly associated with the development of baldness or generation of different clinical phenotypes.
Ha
Seog-Jun
SJ
Department of Dermatology, St. Paul's Hospital, The Catholic University of Korea, 620-56 Junnong 2-dong, Dongdaemun-ku, 130-709, Seoul, South Korea.
Kim
Jung-Soo
JS
Myung
Jae-Wook
JW
Lee
Hyun-Jeong
HJ
Kim
Jin-Wou
JW
D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000235:genetics*; D000328:Adult; D000368:Aged; D000505:Alopecia / Q000188:drug therapy / Q000208:ethnology / Q000235:genetics*; D044466:Asian People / Q000235:genetics; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D018120:Finasteride / Q000627:therapeutic use; D005838:Genotype; D006801:Humans; D007723:Korea; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length
D004791:Enzyme Inhibitors; D018120:Finasteride; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase