Single Nucleotide Deletion in a Transcription Factor Binding Site of the F9 Gene Promoter
Yet another rare type of hemophilia B similar to human hemophilia B Leyden (HBL) is believed to be caused by a single nucleotide deletion in the promoter region of the F9 gene.
A study published by PubMed shows that the deletion of a single nucleotide in the transcription factor binding site of the F9 gene promoter can cause a person to suffer from recurring hemorrhagic episodes, and it’s not even the worst part. The same thing is believed to transmit typical signs of the Christmas disease, resulting in a significant reduction in the expression of the mutant promoter.
The nucleotide deletion is revealed at the F9 gene start codon, right at the overlapping DNA binding sites of the hepatocyte nuclear factor 4α (HNF-4α) and the androgen receptor (AR). As a result of this deletion, the binding of HNF-4α is abolished, while the AR binding remains unaffected in the mutated promoter region. According to studies, the deletion of the said nucleotide in the binding site of the F9 gene promoter is the main cause of this rare type of hemophilia B that looks a lot like the rare type known as hemophilia B Leyden (HBL).
