TY - JOUR
T1 - Gene-based association analysis of a large patient cohort provides insights into genetics of atypical femur fractures
AU - Zhou, Wei
AU - As, Joel
AU - Shore-Lorenti, Catherine
AU - Nguyen, Hanh H.
AU - van de Laarschot, Denise M.
AU - Sztal-Mazer, Shoshana
AU - Grill, Vivian
AU - Girgis, Christian M.
AU - Stricker, Bruno H. Ch
AU - van der Eerden, Bram C. J.
AU - Thakker, Rajesh
AU - Appelman-Dijkstra, Natasha M.
AU - Wadelius, Mia
AU - Clifton-Bligh, Roderick J.
AU - Hallberg, Paer
AU - Verkerk, Annemieke J. M. H.
AU - van Rooij, Jeroen G. J.
AU - Ebeling, Peter R.
AU - Zillikens, M. Carola
N1 - Publisher Copyright:
© The Author(s) 2024.
PY - 2024/9/1
Y1 - 2024/9/1
N2 - Several small genetic association studies have been conducted for atypical femur fracture (AFF) without replication of results. We assessed previously implicated and novel genes associated with AFFs in a larger set of unrelated AFF cases using whole exome sequencing (WES). We performed gene-based association analysis on 139 European AFF cases and 196 controls matched for bisphosphonate use. We tested all rare, protein-altering variants using both candidate gene and hypothesis-free approaches. In the latter, genes suggestively associated with AFFs (uncorrected p-values <.01) were investigated in a Swedish whole-genome sequencing replication study and assessed in 46 non-European cases. In the candidate gene analysis, PLOD2 showed a suggestive signal. The hypothesis-free approach revealed 10 tentative associations, with XRN2, SORD, and PLOD2 being the most likely candidates for AFF. XRN2 and PLOD2 showed consistent direction of effect estimates in the replication analysis, albeit not statistically significant. Three SNPs associated with SORD expression according to the GTEx portal were in linkage disequilibrium (R
2 ≥ 0.2) with an SNP previously reported in a genome-wide association study of AFF. The prevalence of carriers of variants for both PLOD2 and SORD was higher in Asian versus European cases. While we did not identify genes enriched for damaging variants, we found suggestive evidence of a role for XRN2, PLOD2, and SORD, which requires further investigation. Our findings indicate that genetic factors responsible for AFFs are not widely shared among AFF cases. The study provides a stepping-stone for future larger genetic studies of AFF.
AB - Several small genetic association studies have been conducted for atypical femur fracture (AFF) without replication of results. We assessed previously implicated and novel genes associated with AFFs in a larger set of unrelated AFF cases using whole exome sequencing (WES). We performed gene-based association analysis on 139 European AFF cases and 196 controls matched for bisphosphonate use. We tested all rare, protein-altering variants using both candidate gene and hypothesis-free approaches. In the latter, genes suggestively associated with AFFs (uncorrected p-values <.01) were investigated in a Swedish whole-genome sequencing replication study and assessed in 46 non-European cases. In the candidate gene analysis, PLOD2 showed a suggestive signal. The hypothesis-free approach revealed 10 tentative associations, with XRN2, SORD, and PLOD2 being the most likely candidates for AFF. XRN2 and PLOD2 showed consistent direction of effect estimates in the replication analysis, albeit not statistically significant. Three SNPs associated with SORD expression according to the GTEx portal were in linkage disequilibrium (R
2 ≥ 0.2) with an SNP previously reported in a genome-wide association study of AFF. The prevalence of carriers of variants for both PLOD2 and SORD was higher in Asian versus European cases. While we did not identify genes enriched for damaging variants, we found suggestive evidence of a role for XRN2, PLOD2, and SORD, which requires further investigation. Our findings indicate that genetic factors responsible for AFFs are not widely shared among AFF cases. The study provides a stepping-stone for future larger genetic studies of AFF.
UR - http://www.scopus.com/inward/record.url?scp=85203246506&partnerID=8YFLogxK
U2 - 10.1093/jbmr/zjae122
DO - 10.1093/jbmr/zjae122
M3 - Article
C2 - 39126371
SN - 0884-0431
VL - 39
SP - 1315
EP - 1326
JO - Journal of Bone and Mineral Research
JF - Journal of Bone and Mineral Research
IS - 9
ER -