SYNDROME
WHO DISCOVERED CRI DU
CHAT SYNDROME?
In 1963, JEROME LEJEUNE described a syndrome consisting of multiple congenital anomalies, mental retardation, microcephaly, abnormal face, and a mewing cry in infants with a deletion of a B group chromosome
(Bp-), later identified as 5p-
WHAT IS CRI DU CHAT
SYNDROME?
Cri-du-chat syndrome is an autosomal deletion syndrome caused by a partial deletion of chromosome 5p and is characterized by a distinctive, high-pitched, catlike cry in infancy with growth failure, microcephaly, facial abnormalities, and mental retardation throughout life.
WHAT CAUSES CRI DU
CHAT?
From a review of 331 published cases, estimated that most cri-duchat syndrome cases are the result of de novo deletions …show more content…
The genital tract is usually normal in females, except for a report of a bicornuate
In males, the testes are often small, but spermatogenesis is thought to be normal. HOW IS IT DIAGNOSED?
FLUORESCENCE IN SITU HYBRIDIZATION
(FISH)
Molecular cytogenetic studies using FISH allow the diagnosis to be made in patients with very small deletions. FISH uses genetic markers that have been precisely localized to the area of interest.
The absence of a fluorescent signal from either the maternal or paternal chromosome 5p regions indicates monosomy for that chromosomal region.
CHROMOSOME
COMPARATIVE
GENOMIC
HYBRIDIZATION (CGH)
Chromosome CGH is capable of screening the entire genome for
DNA copy-number alterations in a single hybridization.
The resolution is limited to approximately 5-10 Mb.
The results cannot be directly mapped onto the genome sequence. SKELETAL
RADIOGRAPHY
oMicrocephaly, retromicrognathia oCranial base malformations
(reduced cranial base angle and malformed sella turcica and clivus) oDisproportionately short third, fourth, and fifth