P368: Design of the ACCEL study: A prospective clinical assessment study in children with hypochondroplasia

Conclusion: This study highlights the complexities of genetic testing and interpretation in hereditary connective tissue disorders (HCTDs), particularly in cases where standardized clinical criteria exist but are not consistently utilized.Our study also highlights variability in testing strategies even for similar presentations.Positive genetic findings played a critical role in confirming diagnoses, while negative results were valuable in both ruling out HCTDs with low pre-test probabilities and supporting diagnoses like hEDS.However, some patients remained without definitive diagnoses, and variants of uncertain significance (VUS) further complicated clinical interpretation.By clarifying the impact of genetic testing on clinical decision-making for HCTDs, our findings offer valuable insights for optimizing testing strategies, counseling, and patient management in clinical practice.