Families

What is OCLN-related disorder?
OCLN-related disorder is a rare genetic condition that affects how the brain develops. It is sometimes called Band-like Calcification with Simplified Gyration and Polymicrogyria (BLC-PMG), or Pseudo-TORCH Syndrome, because the brain changes can look similar to those caused by certain infections during pregnancy, even though no infection is actually present. It is caused by changes in both copies of a gene called OCLN, which makes a protein called occludin that helps seal the tiny blood vessels in the brain.

A quick note: there are actually three different genetic conditions that can all be called "pseudo-TORCH syndrome," each caused by a different gene. This website is specifically about the type caused by changes in the OCLNgene.

How common is it?
This condition is very rare. Fewer than 50 children have been reported in medical literature worldwide since the gene was first linked to the disease in 2010. It has been described in families from many countries, including Egypt, Turkey, India, the United Kingdom, and Canada. It is more common in families where the parents are related to each other.

How is it inherited?
OCLN-related disorder is inherited in an autosomal recessive manner. A child must inherit one faulty copy of the gene from each parent to be affected. Parents who each carry one faulty copy ("carriers") do not have the condition themselves. There is a 1 in 4 chance (25%) that each child they have together could be affected. Genetic testing and counselling for your family are strongly recommended.