This statement is true. The Er blood group system (ISBT 044) was recognized by the International Society of Blood Transfusion (ISBT) in 2019, making it one of the newest. It currently includes two high-frequency antigens: Era and Erb. The antigens are located on the Piezo1 protein, a mechanosensitive ion channel. The Era antigen is present in >99.99% of the population. The very rare Er(a-) phenotype has been identified, and anti-Era antibodies have been associated with severe Hemolytic Disease of the Fetus and Newborn (HDFN), indicating clinical significance. This discovery highlights that new blood group systems are still being found, often through investigation of severe HDFN cases where the causative antibody does not correspond to known systems.

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Zambia

• Joseph Soko – 101 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies