TESTING NEUTRAL THEORISTS : REVISITING HETEROZYGOSITIES AT THE PHOSPHOGLUCOMUTASE LOCUS AND GLUCOSE PHOSPHATE ISOMERASE LOCUS

Abstract A previous examination (6) of the distribution of frequencies of protein polymorphisms at the phosphoglucomutase and glucose phosphate isomerase loci showed a statistical bias against both loci being simultaneously polymorphic. A rebuttal of these findings based on a neutral theory approach to analysis has been published that argues against such a bias. The neutral theory approach is disputed on the grounds that 1) a fundamentally different data set was used and 2) that the data was skewed by the use of inappropriate transforms. Upgrading the original data with new observations confirms the original observation of a statistical bias against both loci being simultaneously polymorphic. A model based on different chemistries associated with different polymorphism can explain the observed distribution of PGM and GPI heterozygosities.