Az X kromoszómán elhelyezkedő, hiperizmoltságra ható gének azonosítása = Identification of Genes Affecting Hipermuscularity on Chromosome X.

A Compact eger mutans hiperizmoltsagat nemcsak az altalunk korabban felterkepezett, a miosztatin genben levő 12 bp-os delecio (MstnCmpt-dl1Abc) hatarozza meg, hanem tovabbi modifikator genek is a genom kulonboző pontjain. A projekt celja a legfontosabb modifikator intervallum leszűkitese volt az X kromoszoman. Az F2 populacion kapott kezdeti eredmenyek azonban felvetettek annak a lehetőseget, hogy nemcsak egy, hanem kettő-, vagy tobb nagyobb hatasu modifikator gen is lehet az X kromoszoman. Ezt azonban csak specialis terkepezesi populacioval lehet kimutatni, mint peldaul az Advanced Intercross Line (AIL). Mialatt ezt a tobbgeneracios keresztezest megvalositottuk, belefogtunk az 1. kromoszoma modifikator terkepezesebe is az F2-n, - amely nem tartozott a projekt feladatai koze - s amely kisse komplikalt feladat volt, az ugyancsak e kromoszoman levő MstnCmpt-dl1Abc hatasa miatt. Miutan elkeszitettuk a MstnCmpt-dl1Abc-ra nezve csak homozigota mutans egyedeket tartalmazo Compact-AIL-K F11 terkepezesi populaciot es elvegeztuk rajta az atlag 5 Mbp-kent pozicionalt keret-markerekkel a terkepezest, kiderult, hogy az AIL terkepezes, az F2-től elterően ket, erős modifikator hatast mutato intervallumot azonosit. E regiok beszűkitese elkezdődott. | The hypermuscular phenotype of the Compact mouse mutant is determined not only by the 12 bp deletion (MstnCmpt-dl1Abc) discovered by us previously in the myostatin gene, but also by further modifier genes across the genome. The aim of the project was to narrow down the most significant modifier interval on Chromosome X. The first F2 mapping results rose the possibility, that not only one, but two-, or more modifier genes with a large effect could reside on Chromosome X. This, however can be shown only by a special mapping population, such as the Advanced Intercross Line (AIL). Meanwhile this multi-generation cross has been generated, we started the modifier mapping of Chromosome 1 (not belonging to the tasks of this project) on the F2, which was a complicated task because of the MstnCmpt-dl1Abc effect on the same chromosome. After producing the Compact-AIL-K F11 mapping population containing exclusively homozygote mutants for the MstnCmpt-dl1Abc, we carried on the mapping with framework markers with an average spacing of 5 Mbp along the Chromosome X. Two modifier intervals with large effect were detected, both of them were different from the major peak detected in the F2 mapping. Narrowing down of these intervals has been started.