Whether this incomplete penetrance is associated with one of the disease genes recently identified in EXT is currently under investigation.
[ncbi.nlm.nih.gov]
[…] sex‐ratio with a preponderance of males among probands in this series (103: 72, p < 0.02) and in all series reported to date (198: 133, p < 0.001) gives support to the variable penetrance
[doi.org]
In affected females in family 2, phenotypic variability and incomplete penetrance were noted.
[ncbi.nlm.nih.gov]