Each of the heritable human traits that we have discussed in recent weeks is monogenIc invariably caused by mutation in the same gene Each of these traits was quite straightforward from a Mendelian perspective Sickle cell disease: autosomal recessive Phenylketonuria: autosomal recessive Huntington's disease: autosomal dominant genetic homogeneity all affected individuals have the same mutation in the same geneEach of the heritable human traits that we have discussed in recent weeks is monogenic Each of these traits was quite straightforward from a Mendelian perspective: invariably caused by mutation in the same gene. Sickle cell disease: autosomal recessive Phenylketonuria: autosomal recessive Huntington's disease: autosomal dominant genetic homogeneity all affected individuals have the same mutation in the same gene