Pc. Chen et al., Lack of association of rare alleles in the HRAS variable number of tandem repeats (VNTR) region with adult glioma, NEURO-ONCOL, 2(2), 2000, pp. 120-124
HRAS rare alleles have been associated with the increased susceptibility to
a variety of cancers. In the present study we examined the hypothesis that
HRAS rare alleles are a risk factor for adult glioma in a population-based
case-control study of adult glioma in six San Francisco Bay Area counties.
We compared the prevalence of rare alleles in the variable number of tande
m repeats region of HRAS in the germline DNA from 73 white adults who had g
liomas with that of 65 controls. Overall, the prevalence of rare alleles in
cases was not different from the prevalence of those in controls according
to two definitions of rare alleles, We found that 25 of 73 (34%) of cases
versus 25 of 65 (38%) of controls had at least one allele that was not 30,
46, 69, or 87 repeats; 4 of 73 (5%) of cases versus 6 of 65 (9%) of control
s carried one or more alleles with 33, 39, 42, 53, 59, 63, 68, 105, or 114
repeats. The proportion of rare alleles was somewhat higher among subjects
with anaplastic astrocytoma, Among women, cases were less likely than contr
ols to have HRAS rare alleles, whereas among men, cases were slightly more
likely to have HRAS rare alleles, but none of these results approach statis
tical significance. Our data do not suggest an excess of HRAS rare alleles
among adult glioma cases.