Gestational trophoblastic disease (GTD) is not considered to be hereditary. It is a group of rare conditions that affect the cells that would normally develop into the placenta during pregnancy. GTD occurs due to abnormal growth of cells in the uterus, and it is not caused by inherited genetic mutations. However, certain risk factors such as age, previous GTD, and certain ethnic backgrounds may increase the likelihood of developing GTD.
Gestational trophoblastic disease (GTD) refers to a group of rare tumors that develop in the cells that would normally form the placenta during pregnancy. These tumors are typically non-cancerous (benign), but in some cases, they can become cancerous (malignant). GTD includes a range of conditions, such as hydatidiform mole (complete and partial), invasive mole, choriocarcinoma, placental site trophoblastic tumor, and epithelioid trophoblastic tumor.
When it comes to the hereditary nature of GTD, it is important to understand that most cases of GTD are not inherited. The majority of GTD cases occur sporadically, meaning they happen by chance and are not passed down from parents to their children. However, there are some rare instances where GTD can have a hereditary component.
Complete hydatidiform mole (CHM) is the most common type of GTD. It occurs when the sperm fertilizes an empty egg, resulting in the absence of fetal tissue and the overgrowth of placental tissue. CHM is not hereditary and does not run in families. It is caused by random errors during fertilization and is not influenced by genetic factors.
Partial hydatidiform mole (PHM) is another type of GTD that occurs when an abnormal sperm fertilizes a normal egg, leading to an abnormal placenta and some fetal tissue. Similar to CHM, PHM is not hereditary and does not have a familial pattern. It is also caused by random errors during fertilization.
However, there are rare cases where GTD can have a hereditary component. In these instances, a genetic mutation may be passed down from parents to their children, increasing the risk of developing GTD. One such genetic mutation is known as the NLRP7 gene mutation. This mutation is associated with familial recurrent hydatidiform mole (FRHM), a condition where women have a higher risk of developing multiple molar pregnancies.
Women with FRHM have a 1 in 4 chance of having a molar pregnancy with each pregnancy. This condition is inherited in an autosomal recessive manner, which means that both parents must carry the mutated gene for their child to be at risk. If both parents carry the NLRP7 gene mutation, each of their children has a 25% chance of inheriting the mutation and being at risk for GTD.
It is important to note that the NLRP7 gene mutation is extremely rare, and the vast majority of GTD cases are not hereditary. Most women who develop GTD have no family history of the disease, and their risk is not influenced by genetic factors.
Genetic counseling can be beneficial for individuals with a family history of GTD or those who have had multiple molar pregnancies. A genetic counselor can assess the risk of hereditary GTD based on the specific genetic mutations involved and provide guidance on family planning options.
In summary, while the majority of gestational trophoblastic disease cases are not hereditary, there are rare instances where a genetic mutation can increase the risk of developing GTD. The NLRP7 gene mutation is one such example, associated with familial recurrent hydatidiform mole. However, it is important to remember that these hereditary cases are the exception rather than the rule, and most GTD cases occur sporadically without a familial pattern.