A new virus specified determinant of hepatitis B surface antigen

One hundred and three samples from hepatitis B surface antigen (HB(s)Ag) positive Californian blood donors were subtyped in immunodiffusion with respect to d/y, w/r and a21, a23, a3. Spur formation with a human antiserum indicated a previously unrecognized determinant q, which was detected in 96 sera (4 a21yw, 15 a23yw, 69 a21dw and 8 adr). Out of 8 sera which by spur formation were demonstrated to lack q, 7 were further subtyped (2 a21dw and 5 a3dw). Hence all 5 a3 dw specimens were demonstrated to lack q, thus indicating that q is specified by the virus. The possible relation of q to x with further implications for the specification of x is discussed.