According to the American Speech-Language-Hearing Association, cleft lip and cleft palate is the most common congenital deformity, affecting 1 out of every 700 children born each year. (Reference 1) Cleft lip and cleft palate abnormalities occur during the fifth week of gestation, when the medial nasal and maxillary processes fail to merge together during fetal facial formation. Genetics and environmental factors such as drugs and toxin exposure can cause cleft abnormalities in the developing fetus.
Genetics
According to MayoClinic.com, cleft lip or cleft palate may be caused by an inherited isolated, genetic mutation or as part of a syndrome in which cleft abnormalities is a symptom of the disease. The inheritance of a mutated gene increases the individual's susceptibility to cleft abnormalities especially in the presence of environmental triggers. (Reference 2) Patau syndrome, also known as triisomy 13, is a genetic disorder in which the individual has an extra chromosome 13. Children with trisomy 13 also have cleft lip or cleft palate, notes Medline Plus. (Reference 3) Other genetic disorders that result in cleft abnormalities include Loeys-Dietz syndrome and Van der Woude syndrome. Individuals with Van der Woude syndrome have a genetic mutation in the IRF6 gene while individuals with Loeys-Dietz syndrome have a genetic mutation of the TGFBR1 or TGFBR2 genes, thereby resulting in cleft abnormalities.
Drug and Toxin Exposure
Drug and toxin exposure during pregnancy may be a causative agent in cleft abnormalities. Illicit drugs such as heroine and cocaine, as well as smoking and alcohol consumption, can lead to cleft lip and cleft palate. According to the Nemours Foundation, research has shown that women who consume heavy amounts of alcohol, five or more drinks in one occasion, during the first weeks of pregnancy are at a higher risk of having babies with cleft abnormalities. (Reference 4) Furthermore, environmental toxins such as mercury and lead may lead to cleft abnormalities.
Medications
According to Medic8.com, the use of certain medications during pregnancy increase the chances of cleft abnormalities in the developing fetus. Anti-epilepsy medications, anticonvulsives as well as benzodiazepines for insomnia and anxiety, steroids and corticosteroids increase the likelihood of cleft abnormalities when used during pregnancy. Furthermore, Medic8.com notes that the use of certain acne medications during pregnancy may also cause the cleft abnormalities in a developing fetus. (Reference 5)
References
- American Speech-Language-Hearing Association: Cleft Lip and Palate: Causes and Number
- Mayo Clinic: Cleft Lip and Cleft Palate Causes Read more: http://www.livestrong.com/article/166409-what-are-the-causes-of-cleft-lip-palate/#ixzz0uyFMufpI
- Medline Plus: Trisomy 13
- Nemours Foundation: Cleft Lip and Palate
- Medic8.com: What are the causes of cleft lip and palate?
