Cri Du Chat Syndrome

Honors Biology Final 2013

What is Cri du chat syndrome?

Cri du chat syndrome is a very rare genetic condition that affects in 1out of 20,000 to 50,000 babies. This condition is also referred to as 5p- syndrome or cat cry syndrome. It is caused by a missing piece of genetic material on the arm of chromosome 5. A geneticist, Jerome Lejeune first found the syndrome in 1963. Today doctors and scientists do not know why this deletion occurs.

What are the symptoms of cri du chat syndrome?

Cri du chat syndrome has many symptoms but one of the most common symptom is a cat like cry that is diagnosed most of the time right at birth. Some other affects would be a downward slant to the eyes, a low birth weight, slow growth, abnormal facial features such as a small head, small jaw, rounded face, wide-set eyes or webbing of the fingers or toes, skin tags and lack of motor skills. An infant with cri du chat syndrome has an increased possibility of developing a heart defect. This condition could lead to life long problems or even be fatal to a new born baby

What causes cri du chat syndrome?

Doctors and scientists still are unsure why the deletion of chromosome 5 happens. In some cases a parent passes a form of chromosomes that are rearranged to the child and that is only about 10% but in other cases piece of chromosome 5 breaks off during the time the sperm or egg are in its developing stage. Once the gamete is fertilized the child will develop the disorder.

Can cri du chat syndrome be inherited?

Cri du chat syndrome is most of the time not inherited due to the fact the deletion is formed during the formation of an egg and sperm or during fetal development. There is a very low chance, about 10% that a baby could inherit this condition.

Is this condition sex- linked?

No cri du chat syndrome is not sex linked due to the fact that most of the deletions are new mutations formed. Scientists often refer to cri du chat syndrome as a genetic accident.

Is cri du chat syndrome recessive or dominant?

Cri du chat syndrome is not considered recessive or dominant because the fact that it is a deletion that occurs at such a random event, it is rarely ever inherited and it is specifically found on chromosome 5.

How and when is a diagnosis usually made?

Babies are diagnosed at birth most of the time because the physical features are more prevalent but cri du chat syndrome can also be diagnosed by a genetic test that will show the missing segment of chromosome 5. The genetic test FISH is one of the tests that will be performed if they are believed to have cri du chat syndrome. Other ways to know is the distinct physical symptoms of this condition or a blood test will show the deletion of the arm of chromosome 5.

Is genetic counseling an option?

Yes, most doctors want you to go to genetic counseling if you previously had a baby with cri du chat syndrome if you are planning on having another child in the future. Genetic counseling can identify the probability and likelihood of passing a certain genetic disease or disorder onto your child due to a change in the genes.

How is cri du chat syndrome treated?

Cri du chat syndrome has no cure but a doctor will help treat or try to manage the symptoms of this condition. A doctor could refer you to genetic counseling in order to test if one of the parents has a change in chromosome 5 for future reference if they would want to have another child. As for the child different types of therapy will be recommended and given such as physical therapy and speech and language therapy. Some children and adults with cri du chat syndrome will use hand gestures or sign language instead of actually speaking. As a child grows older the condition and symptoms may or may not become less noticeable but symptoms vary from person to person.

What are some of the long term complications of cri du chat syndrome?

Long term complications of this condition varies from person to person in their intellectual disabilities and physical problems or physical needs play a big role. Some symptoms may not allow the person to be able to care for themselves. If a person has early and consistent education therapy such as physical therapy and language therapy there is an increased chance of having less complications. Therapy will help the child to be able to achieve the highest potential for themselves. As an adult a person with cri du chat syndrome can develop short stature and scoliosis.

Is gene therapy possible and is there a cure for cri du chat syndrome?

Currently today, 2013, there is no cure for cri du chat syndrome but in the future they hope to be able to cure this syndrome by gene therapy. Gene therapy is a transplantation of normal genes into cells in place of missing or defective ones in order to correct genetic disorders.

What are the demographics for cri du chat syndrome, who does it affect and how common is it?

Cri du chat syndrome is more common in females than males and it also mostly found in people with an ethnic background. It is estimated that this condition affects 1 out of every 20,000 to 50,000 newborns and there are only about 1 or 2 babies born with cri du chat syndrome each year.