This is for understanding genetic disorders that is Cri du chat syndrome.

1. CRI-DU CHAT SYNDROME
By :
NINGOMBAM HEROJIT SINGH
MSC.2ND SEMESTER
CLASS ROLL NO. :15
DEPARTMENT OF ANTHROPOLOGY,
MANIPUR UNIVERSITY
AN421: HumanGenetics

2. CONTENTS :-
Introduction
Frequency
Symptoms
Causes
Diagnosis
Treatment
Summary

3. INTRODUCTION :
 First reported by Lejeune and Colleagues in 1963.
 It is a structural chromosomal disorder.
 It is also known as 5p deletion syndrome or 5p minus syndrome
because it is caused by the deletion of some part of short arm(i.e. p
arm) of a group B chromosome 5.
(Group B consists of chromosome 4 & 5 according to Denver
system of classification)
 Also known as Cat Cry Syndrome because patients with this syndrome
have a peculiar weak cry which closely resembles the mewing of cat.
FREQUENCY :
 It is a rare genetic disorder.
 Occurs in an estimated 1 in 20,000 to 50,000 new borns.
 More common in females than males.

4. SYMPTOMS:-
 Infants with this condition cry like a weak
mewing of cat (due to problems with the
larynx and nervous system).
 Low birth weight (<2.5kg) and poor growth.
 Small head size (microcephaly) and jaw
(micrognathism).
 Widely-spaced eyes (hypertelorism), low set
ears & rounded face.
 Almost all patients fail to thrive, a few that
survive and live long with have severe
mental retardation.
 Weak muscle tone (hypotonia) in infancy.
 Absence of kidney and spleen.
 Some children are born with heart defect.
 Epicanthal folds, dental malocclusion.

5. CAUSES :-
 It is cause by the partial deletion of the short arm of
chromosome number 5, also called “5p monosomy’’
or "partial monosomy’’
 Approximately 90% of cases results from a randomly
occurring, “de novo deletion” (i.e. occur without
being inherited).
 Chromosomall deletion occurs as a random event
during the formation of reproductive cells.
 And remaining 10-15% are due to deletion inherited
from a parent with a balanced translocation in
which there is no genetic material gained or lost &
no adverse affect.
 But, it is become unbalanced when they passed to
the next generation because some genetic material
from chromosome 5 is lost. So, the child will have
Cri-du chat syndrome.

6. DIAGNOSIS :-
 Typically diagnosed by a doctor at birth.
 Suspected by clinical features, specially by high pitched cry.
 G-banded karyotyping may be performed. (i.e. missing portion of the short arm of
chromosome 5 can be seen)
 And more detailed type of genetic test called FISH (Fluorescence in situ hybridization)
analysis can be used. It’s detection rate for this disorder is approximately 99%.
Treatment :
 No Specific treatment is available for this
syndrome (as the brain damage occurs at
the early stages of embryo development).
 Children born with this condition require
ongoing support from a team made up of
the parents, therapists, medical &
educational professions (to achieve his or
her maximum potential).

7. Summary:
 Rare genetic disorder that occurs in chromosome structure.
 Also known as 5p deletion Syndrome/ 5p minus syndrome/cat cry
Lejeune syndrome.
 It is characterised –
 by the presence of cat-like Cry.
 by facial abnormalities and heart defect.
 also include failure to thrive, hypotonia, neurodevelopmental delay and
others.
 Cause by partial deletion of the short arm of chromosome number 5.
 Diagnosis is based on karyotyping to find the chromosomal abnormalities.
 Treatment is based on treating life-threatening conditions after birth.

8. “ THANK YOU ”