In a case report from France, two siblings with peanut allergy and HαT reacted at lower doses of peanut allergen and had higher specific IgE (sIgE) to both whole peanut and Ara h2 and h6 components as compared to a third sibling from the same family who also had peanut allergy but not HαT, suggesting that HαT and increased α-tryptase may contribute to a more severe FA phenotype (20). The gene discussed is IGHE; the disease is peanut allergic reaction.