POLH
DNA polymerase eta
Normal Function
Health Conditions Related to Genetic Changes
Xeroderma pigmentosum
Several variants in the POLH gene have been found to cause a condition called xeroderma pigmentosum. In particular, POLH gene variants cause the variant type of xeroderma pigmentosum (XP-V). Like the other forms of xeroderma pigmentosum, XP-V is characterized by an increased sensitivity to UV rays from sunlight. However, this form of the disorder is typically not associated with neurological abnormalities, such as delayed development and hearing loss.
Most POLH gene variants prevent the production of any detectable DNA polymerase eta. A loss of this enzyme prevents cells from replicating damaged DNA effectively. Without this mechanism for tolerating DNA damage, errors resulting from exposure to UV rays accumulate in genes that control cell growth and division. These errors cause cells to grow too fast and in an uncontrolled way. As a result, people with XP-V have an increased risk of developing skin cancer in areas where the skin is exposed to sunlight.
More About This Health ConditionRelated Conditions
Xeroderma pigmentosum
Health Conditions Related to Genetic Changes
Several variants in the POLH gene have been found to cause a condition called xeroderma pigmentosum. In particular, POLH gene variants cause the variant type of xeroderma pigmentosum (XP-V). Like the other forms of xeroderma pigmentosum, XP-V is characterized by an increased sensitivity to UV rays from sunlight. However, this form of the disorder is typically not associated with neurological abnormalities, such as delayed development and hearing loss.
Most POLH gene variants prevent the production of any detectable DNA polymerase eta. A loss of this enzyme prevents cells from replicating damaged DNA effectively. Without this mechanism for tolerating DNA damage, errors resulting from exposure to UV rays accumulate in genes that control cell growth and division. These errors cause cells to grow too fast and in an uncontrolled way. As a result, people with XP-V have an increased risk of developing skin cancer in areas where the skin is exposed to sunlight.