Is Sanfilippo Syndrome hereditary?

Is Sanfilippo Syndrome hereditary?

Sanfilippo Syndrome, also known as mucopolysaccharidosis type III (MPS III), is a rare genetic disorder that affects the metabolism of complex sugars called mucopolysaccharides. It is characterized by the progressive accumulation of these sugars in various tissues and organs of the body, leading to severe neurological and physical symptoms.

Genetic Basis:

Sanfilippo Syndrome is inherited in an autosomal recessive manner, which means that both parents must carry a mutated gene for the disorder to be passed on to their children. The syndrome is caused by mutations in one of the four genes (SGSH, NAGLU, HGSNAT, or GNS) responsible for producing enzymes that break down mucopolysaccharides.

Mode of Inheritance:

Each parent of an affected individual typically carries one copy of the mutated gene, but they do not show any symptoms of the disorder themselves. When both parents are carriers, there is a 25% chance with each pregnancy that their child will inherit two copies of the mutated gene and develop Sanfilippo Syndrome.

Types of Sanfilippo Syndrome:

There are four subtypes of Sanfilippo Syndrome, each associated with a specific gene mutation:

• Sanfilippo Syndrome Type A (MPS IIIA): Caused by mutations in the SGSH gene.


• Sanfilippo Syndrome Type B (MPS IIIB): Caused by mutations in the NAGLU gene.


• Sanfilippo Syndrome Type C (MPS IIIC): Caused by mutations in the HGSNAT gene.


• Sanfilippo Syndrome Type D (MPS IIID): Caused by mutations in the GNS gene.

Prevalence:

Sanfilippo Syndrome is considered a rare disorder, with an estimated incidence of 1 in 70,000 live births. However, the prevalence may vary among different populations.

Genetic Testing and Counseling:

If there is a family history of Sanfilippo Syndrome or suspicion of being a carrier, genetic testing can be performed to identify mutations in the relevant genes. Genetic counseling is highly recommended for individuals or couples considering having children, as it can provide valuable information about the risk of passing on the disorder.

Conclusion:

Sanfilippo Syndrome is a hereditary disorder caused by mutations in specific genes involved in mucopolysaccharide metabolism. It follows an autosomal recessive pattern of inheritance, meaning both parents must carry a mutated gene for their child to be affected. Genetic testing and counseling play crucial roles in understanding the risk and making informed decisions regarding family planning.