challenge: What is a notable characteristic of the pathogenic variants that cause Hereditary Folate Malabsorption (HFM)?
  
  A. They usually result in a complete loss of the PCFT protein or complete loss of function
  B. They often result in a partial gain of function of the PCFT protein
  C. They are typically inherited from non-consanguineous parents
  D. They are only found in individuals of Puerto Rican ancestry
  Answer: 