Final answer:
Rett Syndrome is a genetic disorder caused by mutations in the MECP2 gene, leading to neuron death and neurological impairments. Common causes of death include respiratory complications, such as pneumonia. Unlike some genetic disorders, Rett Syndrome does not follow a dominant lethal inheritance pattern but can nonetheless shorten lifespan.
Step-by-step explanation:
Rett Syndrome is a rare genetic neurological disorder that affects brain development, resulting in severe cognitive and physical impairments. It is mainly found in females and is caused by mutations in the MECP2 gene located on the X chromosome. This disorder leads to the death of neurons due to the production of an abnormal protein. As a result, an abnormally low level of a neurotransmitter affects the area of the brain that controls movement, seriously affecting motor functions.
The most common cause of death for individuals with Rett Syndrome is related to respiratory complications, with pneumonia being particularly prominent. Severe seizures and cardiac irregularities may also contribute to mortality. In terms of genetics, dominant lethal inheritance patterns are rare, and are described in disorders like Huntington's disease, which appear later in life and affect an individual's lifespan after they have had the chance to reproduce.
By contrast, recessive lethal inheritance patterns, as seen in diseases like Tay-Sachs, lead to early childhood death and prevent the passage of genes to subsequent generations. With such diseases, carrier parents may pass on the defective allele, resulting in fatal outcomes for the offspring. In the case of Rett Syndrome, while longevity can be shortened, many individuals live into middle age.