SLC19A2 and Thiamine-responsive megaloblastic anemia: Diagnostic Signposting: The presence of specific extra-pancreatic features serves as a powerful “diagnostic filter” to narrow the candidate genes before sequencing results are available: Megaloblastic Anemia + Deafness: Strongly suggests Thiamine-Responsive Megaloblastic Anemia (TRMA) caused by SLC19A2 mutations.