Korean J Obstet Gynecol.  2002 Jun;45(6):990-993.

Allele distribution of FMR1 gene in Korean women

• Song KC
• Kim GJ
• Whang YJ
• Choi SR
• Lee SP
• Whang BC
• Lee ED

Abstract

OBJECTIVE
Fragile X syndrome is the most common form of familial mental retardation, attributable to (CGG)n expansion in the FMR1 gene. This study was undertaken to ascertain the distribution of FMR1 CGG repeat in the general Korean women and to identify ethnic difference in FMR1 CGG repeat number. Material and METHOD: Between January 1999 and December 1999, we evaluated 1,000 low risk women who visited Gachon Medical School Hospital. DNA samples were extracted from the venous bloods by routine methods, and G-C specific Polymerase Chain Reaction (PCR)s were performed to evaluate FMR1 CGG repeat number.
RESULTS
Mean FMR1 CGG repeat number was 26.9 (6-50), single PCR bands were detected in 776 cases (77.7%). There were two more bands in 22.3% of the cases. Most of the cases are located between 21 and 35 repeats, especially 21-25 repeats. The pattern of distribution of CGG repeat is dispersed. In 13 cases, we could not obtain the PCR results.
CONCLUSION
Low risk of transmission rate of the FRX in Korea can be expected.

Keyword

FMR1; polymerase chain reaction (PCR); Southern blotting

MeSH Terms

Alleles*
Blotting, Southern
DNA
Female
Fragile X Syndrome
Humans
Intellectual Disability
Korea
Polymerase Chain Reaction
Schools, Medical
DNA