Abstract
To develop a genetical diagnosis for skeletal malocclusion, we explored gene(s) regulating the anteroposterior length of the maxilla by the method of Quantitative Trait Locus (QTL) analysis using SMXA Recombinant Inbred (RI) strain mice. Anteroposterior lengths between the anterior border of the incisor pore and posterior border of the basisphenoid in the maxilla of 21 SMXA RI Strains mice at 90 days of age were measured. The maxilla of the SMXA-8 strain was the largest (11.5 mm) and that of SMXA-24 was the smallest (10.4 mm) in 21 strains. As the maxilla sizes of SMXA RI strain mice formed a continuous distribution between 11.5 mm and 10.4 mm, the data was regarded as the value of the quantitative trait. The strain distribution pattern reported in the previous study and the value of the quantitative trait were used in the QTL analysis for the whole genome using the Map-Manager QTb 28 software. Based on the result of QTL analysis, we obtained significant values on chromosome 10 and 11. Around the marker D 10 Mit 70 mapped at 57.9 cM from the centromere on chromosome 10, the LOD score showed 2.9 with a suggestive level and around the marker D 11 Mit 152 and D 11 Mit 163 mapped at 9.8 and 13.1 cM, respectively on chromosome 11, the LOD scores showed 5.8 with a significant level.
These results suggest that the major gene(s) regulating the anteroposterior length of the mouse maxilla are located on chromosomes 10 and 11.
