A new beta 2 microglobulin mutation found in a melanoma tumor cell line.
Beta2 microglobulin mutations are an important mechanism for HLA class I total loss, (phenotype No. I) and have been described in colon carcinomas, melanomas and lymphomas. We describe a new beta2 microglobulin mutation detected in the melanoma cell line GR-34. The new mutation reported here was identified as a deletion of 4 bases (TTCT) in the highly repetitive sequence CTCTCTCTTTCT located in the leader sequence of the beta2 microglobulin gene at codon 15-16 of exon 1. The mutation produces a frameshift in the open reading frame sequence with the appearance of a stop codon at position 42. We also demonstrate that the second beta2 microglobulin gene is deleted. Comparisons with beta2 microglobulin mutations in other tumor cell lines suggest a mutation hot spot in exon 1.
Departamento Análisis Clinicos, Hospital Universitario Virgen de las Nieves, Granada, Spain.
B
B
Pérez
R
R
Benitez
M A
MA
Fernández
M R
MR
Oliva
J L
JL
Soto
S
S
Serrano
M A
MA
López Nevot
F
F
Garrido
D000368:Aged; D001483:Base Sequence; D002461:Cell Line, Transformed; D006801:Humans; D008297:Male; D008545:Melanoma / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D014407:Tumor Cells, Cultured; D001613:beta 2-Microglobulin / Q000235:genetics*
D001613:beta 2-Microglobulin