Tongue rolling is often cited as a classic example of a simple genetic trait. In general, the ability to roll your tongue is considered to be an autosomal dominant trait. This means that if one parent has the ability to roll their tongue, there is a higher chance that their offspring will also be able to roll theirs.
The genetic basis for tongue rolling is linked to a specific allele that is dominant over the non-rolling allele. Consequently, individuals with at least one copy of the rolling allele (RR or Rr) can roll their tongues, while only those with two copies of the non-rolling allele (rr) cannot. However, it’s important to note that while this trait is commonly associated with simple Mendelian genetics, the reality can be more complex due to environmental factors and variations in genetic expression.
In conclusion, while the ability to roll your tongue is typically thought to be autosomal dominant, genetics can be intricate, and not everyone fits perfectly into these categories. Genetic diversity and penetrance play significant roles in how such traits are expressed in different individuals.