Haemophilia A is an X-linked recessive bleeding disorder characterised by deficiency of coagulation factor VIII (FVIII). [1] The disorder can be classified according to procoagulant levels of FVIII: patients with severe haemophilia A have levels of <1 IU/dL, those with moderate disease 1-5 IU/dL, and those with mild disease 5-40 IU/ dL. The disorder mainly affects males, at a rate of 1 in 5 000-10 000 worldwide. [1,2] The 2017 World Federation of Hemophilia survey [3] reported that 149 764 individuals were affected by haemophilia A globally, with only 1 848 reported in South Africa (SA). Haemophilia A is underdiagnosed in SA, as in many other developing countries, owing to a lack of access to diagnostic expertise. [4] There is currently only one genetic testing facility, which services all the haemophilia A treatment centres in SA. [4] Genetic research on haemophilia is therefore limited in SA, [4] as evident from the FVIII gene (F8) variant database, to which SA has made no contribution. [5] Genetic testing is of paramount importance in the comprehensive treatment plan for haemophilia A, since mutations in F8 are the cause of the disorder. Furthermore, F8 mutations may be associated with the development of FVIII inhibitors, [6] and variant detection allows for prenatal and carrier detection to enable genetic counselling of haemophilia A families. [7] According to the literature, 45% of all severe haemophilia A cases are associated with an inversion in intron 22 (inv22) of F8. [8,9] Based on gene expression, an mRNA conventional inv22 polymerase chain reaction (PCR) screening method was developed to allow rapid detection of inv22. [10] This method assumes the presence of an additional exon, called exon 23c, contained in the inv22 mutant FVIII transcript. [11] Exon 23c was found to be spliced to exon 22 of F8 in unrelated haemophilia A patients. [10] Objectives To detect the presence of inv22 in the haemophilia A population of central SA and potential haemophilia A carriers. This open-access article is distributed under Creative Commons licence CC-BY-NC 4.0.