Figure 1. GSTM1 detection using PCR

Ethidium bromide stained 3% agarose gel showing PCR products of the 293 bp corresponding to the normal presence of the allele of the GSTM1 gene. The PCR fragment of 583 bp was obtained from the CYP1A1 gene as a control of DNA sample. "M" is DNA size marker. Lane 1 is the result from a normal individual with a homozygous deletion of the GSTM1 allele and in lanes 3 and 5 are shown a homozygous deletion from patients with pterygium. In lanes 2 and 4 are shown the results from a normal individual and the patient with pterygium with normal GSTM1 alleles, respectively.