Transforming growth factor (TGF) beta1 is a growth factor which has multiple functions including the promotion of matrix deposition during wound healing and scar formation. Gene polymorphisms within or close to the 5' region of TGFbeta1 have been identified; three in the upstream region, one in the non-translated region, two in the signal peptide sequence and one in a region of the gene coding for the precursor protein. We have developed a method using 14 polymerase chain reaction-sequence-specific primer reactions to characterise six of these polymorphisms. In the upstream region, both forward and reverse allele-specific primers were used to demonstrate the cis/trans orientation of alleles at adjacent polymorphisms (haplotypes). We report the allele and genotype frequencies of TGFbeta1 genes in two sets of UK Caucasoid control subjects.