Introduction: Classification systems in relation to scoliosis have been a hallmark for the clinician in the development of therapeutic options. The triple curve pattern with three distinct lateral curvatures of approximately equal severity has been recognised as distinct and, potentially, unique in its presentation. From a large population of families with FIS, a subpopulation of families with a triple curve pattern was evaluated in order to determine if this curve pattern is distinct on a genetic level.

Methods: With IRB approval, a sample of families with FIS (202 families, 1198 individuals) were recruited and underwent a genomic screen. The results were analysed using a model independent linkage analysis (SIBPAL). A subgroup of FIS families with at least one member having a triple curve was identified (six families, 32 individuals). After initial linkage analysis, the group underwent further fine mapping analysis utilising a battery of SNPs.

Results: Analysis of the data from the genomic screen on the triple curve subgroup revealed significant areas on chromosome 10 when analysed qualitatively and quantitatively in either a single-point or multipoint fashion.

Conclusion: The utilization of clinical data to discern potential relevance of specific genetic loci in the aetiology of FIS has resulted in an area on chromosome 10 that is significant (p < 0.01). The relatively small population of families within this subgroup coupled with the strength of the data suggests a unique genetic etiological factor associated with the formation of a triple curve in FIS.