Is Door Syndrome hereditary?

Door Syndrome is a rare genetic condition caused by pathogenic variants in the TBC1D24 gene, which follows an autosomal recessive inheritance pattern. This means that for a child to be affected by Door Syndrome, they must inherit one mutated copy of the gene from each parent, who are typically asymptomatic carriers.

Is Door Syndrome hereditary?

Yes, Door Syndrome is a hereditary condition, meaning it is passed down through families via genetic material. It is classified as an autosomal recessive disorder. Because it is not X-linked or mitochondrial, the risk is distributed equally regardless of the biological sex of the child. When both parents are carriers of a TBC1D24 mutation, there is a 25% chance with each pregnancy that the child will be born with Door Syndrome.

What is the role of genetic testing and counseling?

Genetic testing is the gold standard for confirming a diagnosis of Door Syndrome. Molecular genetic testing, specifically sequencing of the TBC1D24 gene, can identify the specific mutations responsible. Because this condition is rare, genetic counseling is vital for families to understand the inheritance risks and explore reproductive options. Key aspects of the genetic counseling process include:

• Reviewing family history to determine the likelihood of carrier status in siblings or extended relatives.


• Discussing prenatal diagnostic options, such as chorionic villus sampling (CVS) or amniocentesis.


• Explaining the availability of preimplantation genetic testing (PGT) for future pregnancies.


• Clarifying that de novo (spontaneous) mutations are rare in Door Syndrome, as most cases arise from inherited carrier traits.

How do parents manage the risk of recurrence?

For families who have already had a child with Door Syndrome, the risk of recurrence in future pregnancies is 25%. Currently, 13 people with Door Syndrome have joined the DiseaseMaps community, providing a space to share experiences with the diagnostic journey. If you are planning a pregnancy, consider the following:

• Consult a clinical geneticist to confirm the specific TBC1D24 variant.


• Request carrier screening for your partner if you have a known family history.


• Inquire about reproductive technologies that can help avoid passing the condition to future generations.

Next steps

• Schedule a consultation with a board-certified genetic counselor.


• Connect with the 13 members in the DiseaseMaps community to share experiences and resources.


• Request a referral to a pediatric neurologist or geneticist familiar with rare neurodevelopmental disorders.

Medical disclaimer: This information is for educational purposes only and does not replace professional medical advice, diagnosis, or treatment; always seek the advice of your physician or qualified health provider with any questions regarding a medical condition.

References

• OMIM (Online Mendelian Inheritance in Man): Entry #220500 (DOOR Syndrome).


• NIH GARD (Genetic and Rare Diseases Information Center): DOOR syndrome overview.


• Orphanet: Rare disease database entry for DOOR syndrome.


• PubMed: Clinical literature regarding TBC1D24-related disorders and their genetic etiology.