Fig. 1

Genetic testing for a female patient (indicated by an arrow) with severe hemophilia A. a Cytogenetic analysis identifies a 45,X [22]/46,X,idic(X)(q21) [8] mosaicism, indicating at least one F8 allele loss. b MLPA analysis for the F8 gene of the patient detects only copy of exon 23–26 peaks indicating an exon 1–22 deletion in the allele on her “morphologically-normal” X-chromosome. MLPA for the patient’s mother detects about 1/2 DNA dosage of exon1-22 indicating a carrier of exon 1–22 deletion. Arabic numbers, the exon numbers of the F8 gene. “c”, the internal controls used in MLPA. “?”, an unexpectedly amplified peck which is not illustrated in the instruction of the MLPA FVIII kit, SALSA P178. “*”, loss of one copy in exons. “▼”, loss of two copies in exons