Genetic factors and clinical significance of acanthosis nigricans in obese Japanese children and adolescents.
OBJECTIVE
To clarify the clinical significance of acanthosis nigricans (AN) and the association of gene polymorphisms in the ss2- and ss3-adrenergic receptors (B2ADR and B3ADR) in Japanese obese children and adolescents.


METHODS
Seventy obese subjects (56 boys, 14 girls) from 5 to 19 y of age were examined as to clinical features. Genetic analyses were performed in 83 obese subjects (61 boys, 22 girls), 2 to 17 y of age. Typing of gene polymorphisms in B2ADR and B3ADR was achieved by polymerase chain reaction (PCR) of genomic DNA and restriction fragment-length polymorphism analysis (PCR-RFLP).


RESULTS
The group with AN (n = 30) had higher values for percent overweight, BMI, waist circumference, fasting insulin, HOMA-R, leptin and PAI-1 than the AN-negative group (n = 40), but there were no significant differences in age, sex or percent body fat between the two groups. The prevalences of B2ADR Gly16 and B3ADR Arg64 were significantly higher in AN-positive (n = 26) than in AN-negative (n = 57) subjects. In addition, the AN frequency was significantly higher in the group with both Gly16 and Arg64 than in the group with neither of these alleles (55.6% vs 12.5%, p < 0.05).


CONCLUSIONS
We demonstrate that AN is a useful clinical marker for the severity of obesity associated with a high BMI, and that B2ADR Gly16 and B3ADR Arg64 are associated synergistically with AN in obese children and adolescents.
Miura
Naoko
N
Department of Paediatrics, Tokyo Women's Medical University, Daini Hospital, Tokyo, Japan.
Ikezaki
Ayako
A
Iwama
Saika
S
Matsuoka
Hisafumi
H
Ito
Keiko
K
Sugihara
Shigetaka
S
D000052:Acanthosis Nigricans / Q000453:epidemiology* / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D044466:Asian People; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D004247:DNA / Q000032:analysis; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D006801:Humans; D007564:Japan / Q000453:epidemiology; D020738:Leptin / Q000097:blood; D008297:Male; D009765:Obesity / Q000453:epidemiology*; D012150:Polymorphism, Restriction Fragment Length; D011863:Radioimmunoassay; D018343:Receptors, Adrenergic, beta-2 / Q000235:genetics*; D022702:Receptors, Adrenergic, beta-3 / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D020738:Leptin; D018343:Receptors, Adrenergic, beta-2; D022702:Receptors, Adrenergic, beta-3; D004247:DNA