Cri du Chat Syndrome

Description

Cri du Chat Syndrome, also known as 5p- syndrome, is a rare genetic disorder characterized by a distinctive cat-like cry in infants. This syndrome affects various physical, cognitive, and developmental aspects. This blog post will delve into the intricacies of Cri du Chat Syndrome, exploring its signs, causes, diagnosis, management, and strategies for thriving with this condition.

Genes Involved

Cri du Chat Syndrome is caused by a deletion of genetic material on the short arm of chromosome 5. This deletion involves several genes, including:

TERT: This gene plays a role in telomere maintenance, which are protective caps at the ends of chromosomes.
CTNND2: This gene is involved in cell-to-cell communication and development.
SEMA5A: This gene is associated with neuronal development and function.
Other Genes: The deleted region also encompasses several other genes whose roles are still being studied.

Recognizing the Signs and Symptoms

Cri du Chat Syndrome presents with a range of symptoms that vary in severity from person to person. Some common signs and symptoms include:

Distinctive Cat-like Cry: The characteristic high-pitched, cat-like cry in infants is often the first sign of Cri du Chat Syndrome. This cry is caused by abnormalities in the larynx.
Delayed Development: Children with Cri du Chat Syndrome may experience delays in their physical, cognitive, and speech development. This can include slow motor skills, language difficulties, and intellectual disabilities.
Facial Features: Individuals with this syndrome may have distinctive facial features such as a small head size (microcephaly), widely spaced eyes (hypertelorism), a flattened nasal bridge, and a low-set, small ears.
Heart Defects: Congenital heart defects are common in Cri du Chat Syndrome, such as ventricular septal defects (VSD) or patent ductus arteriosus (PDA).
Gastrointestinal Issues: Some individuals may have feeding difficulties, gastroesophageal reflux, or constipation.
Other Features: Cri du Chat Syndrome can also involve various other physical features like a single palmar crease, small hands and feet, and a weak muscle tone (hypotonia).

Causes

Cri du Chat Syndrome is caused by a chromosomal abnormality known as a deletion. In most cases, this deletion occurs spontaneously during the formation of egg or sperm cells. This means that it‘s not usually inherited from parents.

The deletion on chromosome 5 can vary in size, and the severity of the syndrome often correlates with the size of the deleted region. In rare cases, the deletion can be inherited from a parent with a balanced translocation.

Inheritance/recurrence risk

Inheritance or Recurrence Risk

The majority of Cri du Chat Syndrome cases are not inherited. However, there is a small risk of recurrence if a parent carries a balanced translocation. In these cases, genetic counseling is essential to assess the risk and provide informed guidance.

WES Whole Exome Sequencing