Canavan Disease Pedigree Chart

Canavan Disease is a rare genetic disorder that affects the brain and nervous system. It is caused by mutations in the ASPA gene, which leads to a build-up of a substance called N-acetylaspartic acid (NAA) in the brain. This build-up damages the myelin sheath, the fatty substance that surrounds and protects nerve cells, leading to progressive degeneration of the brain.

Canavan Disease is an autosomal recessive disorder, meaning that both parents must pass on a copy of the mutated gene for a child to develop the disease. Individuals with only one copy of the mutated gene are carriers and do not exhibit any symptoms of the disease. Symptoms of Canavan Disease typically appear in infancy and may include developmental delays, weak muscle tone, and intellectual disability.

Canavan Disease Pedigree Chart

Creating a Pedigree Chart for Canavan Disease

A pedigree chart is a visual representation of a family’s genetic history that can help identify patterns of inheritance for genetic disorders like Canavan Disease. To create a pedigree chart for Canavan Disease, start by identifying individuals in the family who have been diagnosed with the disease. These individuals will be represented by filled-in symbols on the chart.

Next, identify individuals who are carriers of the mutated gene but do not have symptoms of the disease. These individuals will be represented by half-filled symbols on the chart. Finally, identify individuals who do not carry the mutated gene and are not at risk for developing Canavan Disease. These individuals will be represented by unfilled symbols on the chart.

Interpreting a Canavan Disease Pedigree Chart

When analyzing a Canavan Disease pedigree chart, look for patterns of inheritance that can help determine the risk of passing on the mutated gene to future generations. If both parents are carriers of the mutated gene, each child has a 25% chance of inheriting two copies of the mutated gene and developing Canavan Disease.

It is important to consult with a genetic counselor when interpreting a Canavan Disease pedigree chart to understand the risk of passing on the mutated gene and to make informed decisions about family planning. By creating and analyzing a pedigree chart, families affected by Canavan Disease can better understand their genetic risk and take steps to manage and prevent the disease in future generations.