[Detecting and identifying 3 novel single nucleotide polymorphisms in DNA sequence of epidermal growth factor precursor from Buyi and Han individuals].

Objective: To examine the single nucleotide polymorphism (SNP) distributed in exon 20, 21 and intron 20 of epidermal growth factor precursor gene (preproEGF) of Buyi and Han individuals.

Methods: Eleven primer sets were designed and synthesized for PCR, that genomic DNA of Buyi or Han individual was used as the template, to amplify and sequence respectively the large fragment DNA from preproEGF gene. BLAST programs were applied to compare and identify the SNPs from the sequenced PCR products or amplified DNA fragments.

Results: 4.5 kb DNA fragments long over 20th, 21st exon and 20th intron structures of preproEGF gene were got by PCR respectively from genomic DNAs of Buyi and Han individuals. Results of DNA sequencing showed two SNPs in 4. 5 kb fragment of Han individual, of which one was sited at C86380T of preproEGF gene and another positioned at 84580 bp (T/-), while one SNP was observed in Buyi individual, which was located at T84329C of preproEGF gene. GenBank dbSNP database showed that C86380T SNP in 20th intron of preproEGF gene has not been reported yet from Han group and other cohorts except it has been reported from European and Sub-Saharan groups; and also that T84329C SNP has not been reported yet from Buyi group although it has been reported from Han group.

Conclusions: Our study demonstrates that the Han individual is with C86380T SNP located in 20th intron of human preproEGF gene; and that the Buyi individual has the T84329C SNP sited in 20th intron of human preproEGF gene. However, another Han SNP (T/-) positioned at 84580 bp need to be further confirmed.