RT Journal Article SR Electronic T1 The genetic control of sparteine and debrisoquine metabolism in man with new methods of analysing bimodal distributions. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 321 OP 329 DO 10.1136/jmg.20.5.321 VO 20 IS 5 A1 Evans, D A A1 Harmer, D A1 Downham, D Y A1 Whibley, E J A1 Idle, J R A1 Ritchie, J A1 Smith, R L YR 1983 UL http://jmg.bmj.com/content/20/5/321.abstract AB Debrisoquine and sparteine tests were carried out in 215 random white British subjects. There is a high degree of correlation between the urinary 'metabolic ratios' of the two drugs. New mathematical techniques have been developed (1) to define phenotypes and (2) to identify the genotypes within the dominant phenotype. The members of 15 families were tested with both debrisoquine and sparteine. The results indicate that persons who are 'poor metabolisers' of sparteine are also 'poor metabolisers' of debrisoquine and are autosomal Mendelian recessives.