Molecular analysis of gene in a population in Southern Brazil: Comparison of four methods.

OBJECTIVES

Fragile X syndrome (FXS) is caused by expansion of the number of cytosine-guanine-guanine (CGG) repeats in the regulatory region of the gene (. The molecular diagnoses of FXS can be performed using two tests based on two different techniques, namely polymerase chain reaction (PCR) and Southern blotting (SB). However, both of these techniques have limitations. The purpose of this study was to evaluate the performance of the commercial FragilEase™ PCR kit for FXS diagnosis comparing to other laboratory methods.

DESIGN

and methods: This study had a retrospective design. We analyzed the performance of the FragilEase™ PCR kit using 90 DNA samples from patients with clinical suspicion of FXS or a family history of the syndrome using capillary electrophoresis and compared with the results obtained for the same samples using PCR, SB, and AmplideX PCR.

RESULTS

FragilEase™ PCR kit displayed high concordance with the results obtained using PCR, SB, and AmplideX PCR regarding the detection of normal, intermediate/gray zone, premutation, and full mutation alleles, as well as female homozygosity and mosaicism. The replicate sizes found using the FragilEase™ PCR assay varied on average by two CGG repeats.

CONCLUSION

FragilEase™ PCR, as well as other commercially available kits, efficiently detect mutations and simplify the workflow in laboratories that performing FXS diagnoses.