Inheritance of ear wax types, ear lobe attachment and tongue rolling ability

The mode of inheritance of ear wax type, ear lobe attachment and tongue rolling ability were studied in 77 families with a total of 293 children. The results clearly showed that the dry ear wax type and the attached ear lobe type represent the homozygous state for two pairs of autosomal recessive genes. The evidence for the same being true regarding the lack of ability to roll the tongue was less conclusive in our material, but this could be due to difficulties in communication between the examined individuals and the examiners.