Which are the causes of Mulibrey Nanism?

Mulibrey Nanism is a rare genetic disorder that affects growth and development. It is characterized by a combination of distinct features including severe growth retardation, muscle weakness, liver disease, and a variety of other abnormalities. The term "Mulibrey" stands for muscle-liver-brain-eye, which are the main systems affected by this condition.

The exact cause of Mulibrey Nanism is a mutation in a gene called TRIM37, which is located on chromosome 17. This gene provides instructions for producing a protein that is involved in various cellular processes, including growth regulation and protein degradation. The mutation in TRIM37 leads to a dysfunctional protein, which disrupts normal cellular functions and contributes to the development of Mulibrey Nanism.

The inheritance pattern of Mulibrey Nanism is autosomal recessive, meaning that an affected individual must inherit two copies of the mutated gene, one from each parent. If both parents carry one copy of the mutated gene, they have a 25% chance of having an affected child with Mulibrey Nanism.

One of the key features of Mulibrey Nanism is severe growth retardation, which becomes evident during early childhood. Affected individuals typically have short stature and a small head size (microcephaly). The growth delay affects both height and weight, resulting in a significantly smaller size compared to their peers.

In addition to growth retardation, Mulibrey Nanism can also cause various other health problems. These may include muscle weakness and wasting, which can lead to difficulties with mobility and coordination. Liver disease is another common feature, characterized by an enlarged liver (hepatomegaly), yellowing of the skin and eyes (jaundice), and abnormal liver function tests.

Furthermore, individuals with Mulibrey Nanism may experience abnormalities in the heart, eyes, and endocrine system. Cardiac abnormalities can include a thickened heart muscle (hypertrophic cardiomyopathy) and heart valve defects. Eye abnormalities may involve a reduced ability to see fine details (visual acuity) and an increased risk of certain eye conditions. The endocrine system abnormalities can lead to hormonal imbalances, resulting in various complications.

While there is currently no cure for Mulibrey Nanism, early diagnosis and management of the associated symptoms are crucial. Treatment typically involves a multidisciplinary approach, addressing the specific needs of each affected individual. Regular monitoring and interventions can help manage the various health issues associated with Mulibrey Nanism and improve the overall quality of life for affected individuals.