Objectives: To evaluate the possible synergistic role of partial galactose metabolism defects, high lactase (LPH) genotype and lactose and galactose ingestion in presenile cataract formation.
Design and methods: 51 patients with idiopathic presenile cataracts and 172 healthy cataract-free subjects were genotyped to determine their galactose-1-phosphate uridyl transferase (GALT) and LPH status. Whole milk, skimmed milk and yoghurt consumption was recorded in 19 cataract patients and 172 controls by questionnaire.
Results: GALT mutations and whole milk consumption increased the risk of cataract formation in high LPH genotype group, but not in lactose intolerant subjects. Logistic regression analysis showed the synergistic effect of GALT and LPH mutations on cataract formation.
Conclusions: High lactase activity genotypes and mutations in galactose-1-phosphate uridyl transferase have a synergistic effect on presenile cataract formation.