MED13L haploinsufficiency syndrome

What causes MED13l haploinsufficiency syndrome?

MED13L haploinsufficiency syndrome is caused by a change (pathogenic variant also called mutation) in one copy of the MED13L __ gene. This gene provides the body with instructions for making a protein that helps the brain and the heart develop correctly.

Like most genes, MED13L comes in a pair (two copies). When one copy of this gene has a pathogenic variant, only one copy is working in the body (haploinsufficiency). Haploinsufficiency of MED13L causes the brain and sometimes the heart to not develop normally. This causes the different features associated with MED13L haploinsufficiency syndrome.

Last updated on 05-01-20

How is MED13L haploinsufficiency syndrome diagnosed?

A doctor may suspect MED13L haploinsufficiency syndrome based on a baby, child, or even adult having the distinctive facial features, speech problems, and intellectual disability common to the syndrome. The diagnosis must be confirmed by finding a pathogenic variant in the MED13L gene through genetic testing, since many other genetic syndromes can cause similar clinical features.

Last updated on 05-01-20

How is MED13L haploinsufficiency syndrome inherited?

In most cases, MED13L haploinsufficiency syndrome is not inherited from a parent, but is instead present for the first time in a person who is diagnosed with the syndrome. This kind of genetic change is known as a de novo pathogenic variant (mutation).

There have been some documented cases in which a person with this syndrome does inherit it from one parent. This may happen if the parent also has MED13L haploinsufficiency syndrome, but it was never diagnosed because the clinical features are mild in the parent. In this case, each child of the parent with MED13L pathogenic variant would have a 50% chance to inherit the syndrome. However, the clinical features in the child may be mild like the parent’s or the features may be more severe. The syndrome can also be inherited when some of the cells in the parent’s body has the pathogenic variant in MED13L , but most do not. In this case, the parent would have no clinical features of the syndrome, but each future child would be at an increased risk to have the syndrome.

Last updated on 05-01-20

How might MED13L haploinsufficiency syndrome be treated?

There is no cure for MED13L haploinsufficiency syndrome. Treatment is based on the type and severity of medical, developmental, and behavioral problems present in the infant, child, or adult with the syndrome. For example, an infant with a heart defect may need surgery to correct the problem. Other possible treatment options include behavioral, speech, and occupational therapy to help the person with MED13L haploinsufficiency syndrome to achieve their fullest potential.

Last updated on 05-01-20

Name: MED13L: Simons VIP Connect Community Url:
Name: MED13L Syndrome Association Url:
Name: MED13L Foundation PO BOX 283
Barrington, NJ, 08007,
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Asadollahi R & cols. Dosage changes of MED13L further delineate its role in congenital heart defects and intellectual disability European Journal of Human Genetics. 2013; 21(10). 1100-1104. Reference Link Van Haelst MM & cols. Further confirmation of the MED13L haploinsufficiency syndrome European Journal of Human Genetics. 2015; 23(1). 135-138. Reference Link MED13L mediator complex subunit 13 like [Homo sapiens (human)] Gene. June 4, 2017; Reference Link Yamamoto T, Shimojima K, Ondo Y, Shimakawa S, and Okamoto N. MED13L haploinsufficiency syndrome: A de novo frameshift and recurrent intragenic deletions due to parental mosaicism American Journal of Medical Genetics. May 2017; 173(5). 1264-1269. Reference Link Adegbola & cols. Redefining the MED13L syndrome Eur J Hum Genet. October, 2015; 23(10). 1308-17. Reference Link Asadollahi R, Zweier M, Gogoll L, Schiffmann R, Sticht H, Steindl K, and Rauch A. Genotype-phenotype evaluation of MED13L defects in the light of a novel truncating and a recurrent missense mutation European Journal of Medical Genetics. September 2017; 60(9). 451-464. Reference Link Kniffin CL. Mental Retardation and Distinctive Facial Features With or Without Cardiac Defects; MRFACD Online Mendelian Inheritance in Man. February 5, 2016; Reference Link

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