Polymorphism in the Sp1 binding site in the first intron of the COL1A1 gene
has been related to increased risk of osteoporosis in several populations.
To overcome the difficulties associated with the use of mismatch oligonucl
eotide primers in the original method for its detection, we developed a pro
cedure involving PCR amplification of a 598-base pair sequence from the int
ron and its digestion with the restriction enzyme Van 91 I. The more freque
nt allele is recognized by the enzyme, whereas the reaction is abolished in
the less frequent allele. Two convenience samples from the population in n
orthern Finland, consisting altogether of 173 individuals, were studied. Th
e overall frequencies were 0.864 for the G and 0.136 for the T allele, with
a heterozygocity of 27.2%. The frequency of the T allele is towards the lo
wer end of the range observed for other European populations.