Medical Genetics It is true than men tend to marry women who are shorter than themselves but that is a phenotypic difference, not a genotypic difference. Since the wives of taller than average men tend to represent the general population of women they wil not have, on the average as many tall genes to pass on to their offspring as their husbandsMedical Genetics It is true than men tend to marry women who are shorter than themselves, but that is a phenotypic difference, not a genotypic difference. Since the wives of taller than average men tend to represent the general population of women, they will not have, on the average, as many "tall" genes to pass on to their offspring as their husbands