hh, or the #Bombay_Blood_Group, is a RARE blood type. This blood phenotype was first discovered in Bombay by Dr. Y. M. Bhende in 1952. It is mostly found in the Indian sub-continent (India, Bangladesh, Pakistan) and parts of the Middle East such as Iran

All around the globe, the instance of a human having a ‘hh’ blood type is one in four million. The incidence is higher in South Asia. While in India, one in 7,600 to 10,000 are born with this type.