SNP Shot: Genomic Insights

Anencephaly is a birth defect where the brain and skull bones don't develop correctly. This happens when the neural tube, which normally forms the brain and spinal cord during early pregnancy, doesn't close completely. Because it's caused by a problem with the neural tube, anencephaly is considered a neural tube defect.

When the neural tube doesn't close as it should, the developing brain and spinal cord are exposed to the amniotic fluid in the womb. This exposure damages the nervous system tissue, causing it to deteriorate. Consequently, individuals with anencephaly are missing significant portions of the cerebrum and cerebellum, brain areas crucial for functions like thinking, hearing, seeing, feeling emotions, and coordinating movement. The skull bones are also either absent or not fully formed.

Due to the severity of these nervous system abnormalities, almost all infants born with anencephaly do not survive; they either die before birth or shortly after, usually within hours or days.

Inheritance:

Most instances of anencephaly are sporadic, meaning they occur without a family history of the condition. In a small number of cases, anencephaly has been observed in multiple family members; however, there's no established inheritance pattern. Parents who have already had a child with anencephaly face a higher chance of having another child with the same condition compared to the general population.