Hemophilia A in a Phenotypically Normal Female with XX/XO Mosaicism

HEMOPHILIA in females has been the subject of a number of reports in recent years.1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Excluding patients who conform to the classic sex-linked mode of transmission and are truly homozygous for the hemophilia gene,5 , 9 , 11 , 12 , 14 , 17 a residual group of apparent females who exhibit varying degrees of clinical disease remains. The deficiency of antihemophilic globulin (AHG, factor VIII) in these persons who are assumed to be heterozygotes has generally been explained on the basis of mutation in the normal X chromosome. Five such persons have had chromosome analyses performed,4 , 6 , 8 , 10 , 16 and in only 110 was an abnormal karyotype detected.It is the purpose . . .