D. Saranath et al., RESTRICTION-FRAGMENT-LENGTH-POLYMORPHISMS OF THE HUMAN N-MYC GENE IN NORMAL HEALTHY-INDIVIDUALS AND ORAL-CANCER PATIENTS IN INDIA, Indian Journal of Biochemistry & Biophysics, 31(3), 1994, pp. 177-183
Southern blot hybridization with N-myc oncogene probes coding for diff
erent regions of the N-myc gene demonstrated three polymorphic restric
tion sites in the Indian population. The SphI and PvuII polymorphic pa
ttern due to the SphI polymorphic site in the second intron and the Pv
uII polymorphic site in the 3'-region of the human N-myc oncogene resp
ectively, was similar to that reported in the Japanese population. The
allelic frequency distribution for SphI polymorphism did not differ s
ignificantly for the S1 and S2 alleles representing presence (allele S
1) or absence (allele S2) of a SphI site. However, the allelic frequen
cy distribution was distorted in the case of PvuII polymorphism, as th
e frequency of P1 allele (0.7) indicating presence of PvuII site, was
higher than the P2 allele (0.3) indicating absence of PvuII site, in t
he Indian population. An additional polymorphic HindIII site localised
in the second intron of the N-myc gene was also observed in both the
Indian oral cancer patients and the normal healthy individuals, indica
ting that this RFLP was not tumor associated and may perhaps represent
N-myc alteration in the Indian population.