226EXPLORING FGFR2 MUTATIONS IN TESTICULAR TUMORS: INSIGHTS FROM TUMOR CELL LINES AND GERM CELL TUMOR SAMPLESVarious skeletal disorders are linked to germline mutations in the fibroblast growth factor receptor (FGFR) gene family, particularly FGFR3 mutations found in tumors. Despite the association of FGFR2 mutations with congenital syndromes, their role in cancer remains uncertain. This study investigated FGFR2 mutation prevalence in 58 tumor cell lines of diverse types and 29 testicular germ cell tumor samples, considering evidence suggesting that gain-of-function mutations drive positive selection in adult spermatogonia. While sequence variations and allelic imbalance in FGFR2 were identified, none of the documented dominant mutations were detected. This study suggests that FGFR2 mutations may not significantly contribute to testicular tumors, and that gain-of-function mutations affecting various proteins have been observedMeera@gmail.comResearch822018FGFR2 mutations, Tumor cell lines, Testicular germ cell tumors, Gain-of-function mutations. Allelic imbalanceDr Meera Balakrishnan*, Dr. Elakkiya KAssistant Professor, Department of Pathology, Sri Lakshmi Narayana Institute of Medical Sciences, Puducherry - 605 502, India