The association between endothelin-1 gene polymorphisms and susceptibility to vitiligo in a Korean population.
BACKGROUND
Vitiligo is a skin disorder affected by genetic, environmental, local and endocrine factors. Endothelin-1, which is expressed by keratinocytes, has paracrine effects on melanocytes, influencing their homeostasis, proliferation and pigmentation. It is thought to play a role in the skin response to 311-nm, narrow-band ultraviolet irradiation.


OBJECTIVE
To investigate the association of endothelin-1 gene (EDN1) polymorphisms with vitiligo in a Korean population.


METHODS
To evaluate the expression of endothelin-1 in cultured human keratinocytes after irradiation with narrow-band ultraviolet B (NBUVB), we performed RT-PCR and ELISA. In addition, we genotyped 312 vitiligo patients and 313 matched-healthy controls, and compared the genotype, allele and haplotype frequencies of EDN1 polymorphisms (intron 4 G/A, rs2071942 and exon 5 G/T, rs5370) between the two groups, using PCR-restriction fragment length polymorphism. The effects of sex, onset age, the presence of autoimmune diseases, family history and clinical type were analysed statistically.


RESULTS
NBUVB induced the expression of endothelin-1 in cultured human keratinocytes. The genotype distributions and allele frequencies of EDN1 polymorphisms did not differ significantly between vitiligo patients and healthy controls. Moreover, the results were not related to sex, onset age, the presence of autoimmune diseases or family history. Interestingly, the haplotype frequencies of EDN1 polymorphisms differed significantly between vitiligo patients and healthy controls. When analysed according to clinical type, the haplotype frequencies in the focal and segmental clinical types differed significantly from healthy controls.


CONCLUSIONS
This study suggests that EDN1 is related to the development of vitiligo in the Korean population.
Kim
Hyun-Jin
HJ
Department of Dermatology, College of Medicine, Seoul, Korea.
Choi
Chun-Pill
CP
Uhm
Yoon Kyung
YK
Kim
Young Il
YI
Lee
Jin-Woo
JW
Yoon
Seo Hyun
SH
Chung
Joo-Ho
JH
Lee
Mu-Hyoung
MH
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000235:genetics* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007231:Infant, Newborn; D015603:Keratinocytes / Q000378:metabolism / Q000528:radiation effects*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012307:Risk Factors; D012867:Skin / Q000473:pathology; D014466:Ultraviolet Rays; D014820:Vitiligo / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
D019332:Endothelin-1