Glycophorin B‐A‐B Variant GP.Mur, a Chaperone for Erythroid SLC4A Transporter, Supports Gas Exchange during Exhaustive Exercise

The main function of glycophorin A is to stabilize protein complex expression of SLC4A (band 3) and to facilitate its Cl − /HCO 3 − antiporter activity across human red blood cell (RBC) membrane. Anion exchange through SLC4A on the RBC surface is physiologically critical for blood CO 2 transport. We previously found that glycophorin B‐A‐B hybrid protein GP.Mur, a special blood type unique to people of Southeast Asian origins, further promotes erythroid expression of SLC4A. People with GP.Mur phenotype not only express more band 3 on their RBCs but also exhibit more efficient blood CO 2 expiration when challenged with a mild stepping exercise test. We have noticed a disproportional number of elite athletes in Taiwan bearing the GP.Mur phenotype. The goal of this study was thus to verify whether GP.Mur expression could indeed support the respiratory function of elite athletes during exhaustive exercise. Here we recruited GP.Mur+ and GP.Mur‐young elite/professional athletes in Taiwan and challenged them with a graded, exhaustive protocol of cardiopulmonary exercise testing (CPET). As revealed by CPET, compared to the athletes lacking the special blood type, GP.Mur+ athletes showed smaller respiratory quotient (RQ) and lower arterial CO 2 tension throughout the graded test before exhaustion. This suggests relative easiness on the respiratory function for athletes with GP.Mur phenotype during exhaustive exercise. We are currently exploring the possibility of utilizing one’s GP.Mur/band 3 expression levels in personalized athletic training. Support or Funding Information Taiwan Ministry of Science & Technology (MOST 108‐2628‐B‐195‐001)