The geneticist named the main symptoms of cat cry syndrome
Cat's cry syndrome is a rare genetic disorder associated with the loss of a portion of the 5th chromosome. Natalia Zakharzhevskaya, a leading geneticist and expert at the Hemotest Laboratory, told Izvestia about the causes, manifestations and diagnosis on May 5, the Day of Awareness about Cat's Cry Syndrome.
"In 80-90% of cases, such chromosomal breakage occurs spontaneously and is not related to inheritance. But about 10% of families develop the syndrome due to an unbalanced translocation," she noted.
According to the expert, the disease occurs in about one in 15-50 thousand newborns, more often in girls. The syndrome got its name because of the characteristic cry of infants, resembling a meow, which is associated with the peculiarities of the structure of the larynx.
The expert clarified that children with this diagnosis may experience developmental delay, low muscle tone, difficulty feeding, as well as characteristic external signs — small head size, wide-set eyes and low-set ears. In some cases, congenital heart defects and hearing disorders are detected.
"The severity of the symptoms largely depends on which part of the chromosome is lost. The larger the deletion, the more pronounced the main manifestations," Zakharzhevskaya explained.
The diagnosis is usually made after birth and confirmed by genetic studies. During pregnancy, it is more difficult to identify the syndrome, since there are no specific markers, but indirect signs on ultrasound are possible.
The expert added that a non-invasive prenatal test can only assess the risk, but does not provide accurate confirmation. According to her, if a diagnosis is suspected, it must be confirmed by diagnostic methods — chorionic biopsy or amniocentesis. The geneticist also noted that the disease itself does not progress, and with early rehabilitation, children can learn basic skills and social adaptation.
"The earlier the diagnosis is made and comprehensive rehabilitation is initiated, the better the quality of life of the child and his relatives," the expert concluded.
Denis Rebrikov, a molecular biologist, geneticist, Doctor of Biological Sciences, Professor of the Russian Academy of Sciences, Vice-rector for Research at Pirogov University, said on March 6 that the risk of having a child with a hereditary genetic disease is about 1%, which is higher than the probability of getting into a car accident within a year. The doctor added that the chance of having a child with disabilities is high in closed ethnic or religious groups.
Переведено сервисом «Яндекс Переводчик»
