J Korean Endocr Soc.  2008 Apr;23(2):117-122. 10.3803/jkes.2008.23.2.117.

CAG Repeats in the Androgen Receptor Polymorphism do not Correlate with Thyrotoxic Periodic Paralysis

• Kim WG
• Kim TY
• Kim JM
• Rhee YS
• Choi HJ
• Kim WB
• Shong YK

• KMID: 2063562
• DOI: http://doi.org/10.3803/jkes.2008.23.2.117

Abstract

BACKGROUND: Thyrotoxic periodic paralysis (TPP) occurs mostly in males, but no studies have addressed the role of androgen in the disease. Hyperinsulinemia can precipitate acute paralysis in TPP patients. CAG repeats in the androgen receptor (AR), an X-linked gene, correlate with serum insulin levels. AIM: To evaluate whether CAG repeats in the AR gene might predict the susceptibility to TPP in Korean male Graves' patients.
METHODS
We evaluated CAG repeat length in a series of 33 male TPP patients and 48 control patients by direct sequencing of the PCR product of the AR promoter site. Control patients were male Graves' patients without a history of paralysis.
RESULTS
The CAG repeat length varied from 15 to 34 (median of 23). The upper quartile of CAG length was equal to or above 26 repeats (long AR). The distribution of long AR was 0.30 in TPP and 0.15 in control patients, respectively (odds ratio, 2.51; 95% confidence interval, 0.92~6.85; P = 0.09).
CONCLUSION
AR gene polymorphisms may not confer genetic susceptibility to TPP in Korean male patients with Graves' disease.

Keyword

Androgen receptor; Polymorphism; Thyrotoxic periodic paralysis

MeSH Terms

Genes, X-Linked
Genetic Predisposition to Disease
Graves Disease
Humans
Hyperinsulinism
Insulin
Male
Paralysis
Polymerase Chain Reaction
Receptors, Androgen
Insulin
Receptors, Androgen

Figure

• 

  Fig. 1 Representative sequences of androgen receptor gene CAG repeat. The CAG repeat began at nucleotide number 87 and end at nucleotide number 149. This meant that 21 CAG repeat was present in the sample.

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  Fig. 2 Distribution of CAG repeats of the promoter lesion of the androgen receptor gene in male Graves' patients with (TPP) or without (GD only) history of thyrotoxic periodic paralysis.

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