Mutation Analysis of COL1A1 and COL1A2 in Fetuses with Osteogenesis Imperfecta Type II/III.

AIM: To analyze COL1A1/2 mutations in prenatal-onset OI for determine the proportion of mutations in type I collagen genes among prenatal onset OI and to provide additional data for genotype-phenotype analyses.

MATERIAL AND

METHODS

Ten cases of severe fetal short-limb dwarfism detected by antenatal ultrasonography were referred to our center. Before the termination of pregnancy, cordocentesis was performed for fetal karyotype and COL1A1/2 gene sequencing analysis. Postmortem radiographic examination was performed at all instances for definitive diagnosis.

RESULTS

COL1A1 and COL1A2 SNP and mutations were identified in all the cases. Among these, one synonymous SNP and four synonymous SNPs were recognized in COL1A1/2, respectively, seven cases have distinct heterozygous mutations and six new COL1A1/2 gene mutations were identified.

CONCLUSION

There has been substantial progress in the identification of the molecular defects responsible for skeletal dysplasias. With the constant increase in the number of identified mutations in COL1A1 and COL1A2, genotype-phenotype correlation is becoming increasingly pertinent.