Public Health News· New Hunan Client, July 23 (Reporter Wang Lu, Correspondent Danni Wu Xinghan) A little boy from Chenzhou, Yuan Yuan (pseudonym), is 3 years old and 8 months old this year, because he still can't speak, his mother took him to Hunan Provincial Children's Hospital for examination. The doctor learned that Yuan Yuan also has an older brother and sister, and the elder sister is relatively normal, but the 9-year-old brother can only call his mother at present, and his cognitive and expression skills are very poor, and the brothers are irritable, like to repeat stereotypical actions, often immersed in their own world, and cannot communicate and play with others normally like children of the same age.
Wang Hua, chief physician of the Department of Medical Genetics of Hunan Provincial Children's Hospital, conducted a comprehensive assessment of Yuanyuan, and believed that Yuanyuan had backward language, long face and ears, and a family history of intellectual disability, and needed to improve the genetic screening for fragile X syndrome. In the end, the genetic results confirmed that Yuan Yuan did indeed suffer from Fragile X syndrome. Considering Yuanyuan's poor family conditions, the Department of Medical Genetics of Hunan Provincial Children's Hospital also conducted free screening tests for Yuanyuan's mother, brother and sister for fragile X syndrome.
Wang Hua suggested that Yuanyuan's parents should go to the Department of Medical Genetics for genetic counseling and prenatal diagnosis when they give birth or their offspring reach the stage of marriage and childbearing, so as to prevent the family from having children with similar diseases again. At the same time, it is reminded that the blood relatives of Yuanyuan's mother also need to go to the genetics department for detailed genetic counseling before giving birth.
Yuanyuan's mother, Ms. Yuan, was very confused, she and her husband were very healthy, there was no problem with the prenatal check-up during pregnancy, and everything was normal when the children were born, why did they get such a disease that they had never heard of?
World Fragile X Syndrome Disease Awareness Day is celebrated on July 22 every year. Professor Wang Hua said that fragile X syndrome is caused by a mutation in the FMR1 gene on the X chromosome, and is a genetic disorder that affects children's intelligence, language, appearance and health. The causative cause is usually a dynamic mutation in the trinucleotide of the FMR1 gene, which is an abnormal amplification of the first exon (CGG)n trinucleotide repeat in the FMR1 gene. When the abnormal amplification reaches a certain amount, it affects the normal development of the brain, which leads to a series of symptoms such as mental retardation. Specifically, when the number of CGG repeats is less than 45, it is normal, between 45 and 54 is intermediate, between 55 and 200 is premutation, and more than 200 is full mutation.
The same gene can cause three completely different types of disease due to different CGG repeats. All-mutant males present with moderate to severe intellectual disability, and females have a slightly weaker all-mutant phenotype; Approximately one-third of male premutation carriers will develop fragile X-related tremor/ataxia syndrome, and 20% of female premutation carriers will have fragile X-related primary ovarian insufficiency. Fragile X syndrome is X-linked and may be asymptomatic or mildly symptomatic in females, but severe in males.
Typical clinical manifestations of the syndrome include:
1. Intellectual disability: manifested as moderate and severe mental retardation, most of which have IQ
2. Language disorder: manifested as severe speech retardation, poor language expression ability, small vocabulary, repetitive speech, slurred speech, slow speech, imitating language, and often talking to oneself.
3. Special features: large head, square forehead, long face, large and protruding jaw, large ears, sunken middle face, high palate arch, thick lips.
4. Large testicles: 50% of patients enter puberty and the testicular volume reaches 30~50ml (the normal value is 20ml).
5. Behavioral disorders: hyperactivity and attention deficit, autism spectrum disorder, manic/aggressive behavior, some patients may have seizures, etc.
There are no exact statistics on the incidence of fragile X syndrome, but it is known to be second only to Down syndrome in its incidence. There is currently no cure for the treatment of the disease, but early intervention and comprehensive treatment can help patients improve their quality of life and reduce symptoms. Early intervention includes language training, behavioral therapy, special education, etc., and comprehensive treatment also includes medication and rehabilitation training.
If parents find that their child has symptoms such as language retardation, mental retardation, and special facial features, they should take their child to the hospital for examination in time for early diagnosis and treatment. At the same time, for families with a family history of heredity; Women who have given birth to children with mental retardation, autism, and abnormal behavior should pay more attention to genetic counseling and prenatal diagnosis to prevent the occurrence of the disease.