Hello, Andrey! Whether and it is known already genetikam, for what 21 I respond h...

[Mia]

Hello, Andrey!
Whether and it is known already genetikam, for what 21 I respond a chromosome? Or still is not present? (Simply it is very interesting!)

[Andrey]

Good afternoon Mia. The chromosome 21 one of the smallest (the greatest is 1, then 2, etc., X too very much greater or big to stati), but on her is available on different data from 150 up to 300 different genes, and everyone for something responds. The role of some genes is well enough studied or investigated, others are not present. If you illness or disease of the Down on this chromosome the critical district which causes this disease at a trisomy has been found out interests. Therefore, the answer to your question - she is responsible for many things:-)

[Julia]

Good evening! It is a little to the previous question... Daughters 2 4. Result of the cytogenetic analysis: a karyotype of lymphocytes of a peripheric blood - 45, XX,-21 (a monosomy on 21 pair). Doctors have told or said, that such case did not meet in an expert or a practice. A question: can describe the given case? Why has arisen given patalogija? Whether longly there live such children? Than it is possible to help or assist the child? Whether there are rehabilitational centers in Moscow where are engaged with such kiddies?
In advance I thank for the answer!

[Andrey]

Uvzhaemaja Julia. Really monosomy on 21 chromosome meets extremely seldom and is described tolko hardly more than 10 cases when at a monosomy 21 child was born alive. At patients with this karyotype the pathology serdechno-vascular system is observed raznoobrznaja, the mental retardation, a pathology of internal organs and as a rule children perish in the first days of a life. However precisely to diagnose a monosomy 21 it is complex or difficult enough - t. To. A chromosome very small it is necessary to use FISH with probes, speptsifichnymi for 21 j chromosomes. It is a lot of cases when this pathology has been diagnosed in 70 h have been denied by the last tsitogenetichekimi analyses. Besides t. To. The chromosome very small, can be observed a translocation of its or her greater part on other, greater or big chromosome on the size, that most likely could occur or happen at your daughter. In the literature it is considered, that children with full a monosomy 21 are not teleorganic and perish at early stages of pregnancy, or right after sorts or labors. In many cases at children with a monosomy 21 it is observed mozaitsizm - t. To. Some cells have 1 chromosome, and the some people 2. The reasons of occurrence of the given pathology can be much but all of them are connected with disturbances of education of sex cells.

[Julia]

Thanks for the answer! I shall a little add... Really translocation is, in very small quantity or amount the part of 21 chromosomes on 7 pair is found out, doctors will investigate or research further our case. But nevertheless the diagnosis: a monosomy. Mozaitsizma is not present. Threats of a life are not present, intimate or cardiac patalogy too, but about a mental retardation - probably yes. Transolakija very small part of a chromosome, and not all cells it or her contain that. Pregnancy desired was, parents healthy, karyotypes in norm or rate. So is in Moscow spets. Establishments for such children?

[Julia]

Excuse for a typing error: a translocation certainly

[Andrey]

Dear Julia, whether unfortunately I cannot tell or say to you is of establishment for such children in Moscow, t. To. I am not there. It is better to you to learn or find out about it or this in the genetic center. Time not cells it or her contain all, all means taki mozaitsizm is. And what sample spent the cytogenetic analysis - about use FISH (fluorescent in situ hybridisation) or not? It is quite probable, that if to take probes from different sites of a chromosome 21 it can is possible to define or determine a karyotype much more precisely.