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Papillary thyroid cancer (PTC) is the most common endocrine malignancy with especially high incidence in Middle Eastern populations. While classical hereditary syndromes explain a minority of cases, the broader germline landscape of non-syndromic PTC remains unclear. Whole-exome sequencing was performed on 245 unselected Saudi PTC patients to identify germline pathogenic or likely pathogenic variants (PVs/LPVs) in cancer predisposition genes. Clinical and molecular characteristics, and family history were integrated to assess phenotypic correlations. Eleven patients (4.5%) harbored germline PVs/LPVs in cancer susceptibility genes including STK11, TP53, BRCA1, BRCA2, FANCA, SLX4, RAD50, MSH6, POLD1 and NF1. Four patients (36.4%) carried PVs/LPVs in canonical FA pathway genes; this increased to five patients (45.5%) when RAD50 was included. Two unrelated patients harbored the same STK11 variant (p.R304Q) without classical Peutz-Jeghers syndrome features. A TP53 hotspot mutation (p.R175H) was identified in a patient with a personal history of gastric cancer, a malignancy associated with Li-Fraumeni syndrome. Notably, the BRCA1 PV detected matches a known Saudi founder mutation in hereditary breast cancer, now observed in PTC. Most germline positive cases lacked syndromic manifestations, underscoring limitations of phenotype or family history-driven genetic testing strategies. These findings suggest that a small subset of non-syndromic PTC cases may carry germline PVs/LPVs in cancer predisposition genes, highlighting the need for broader genetic screening frameworks. Unbiased whole-exome analysis in unselected cohorts can uncover under-recognized genetic risk and guide screening strategies to address the unique hereditary landscape of thyroid cancer in underrepresented populations.