Molecular Genetics and Enzymology Department, Human Genetics and Genome Research Division (HGGR), National Research Centre (NRC), Cairo, Egypt.
Medical Molecular Genetics, HGGR, NRC, Cairo, Egypt.
Mol Genet Genomic Med. 2021 Feb;9(2):e1575. doi: 10.1002/mgg3.1575. Epub 2020 Dec 20.
Hemophilia A (HA) is an inherited X-linked recessive coagulation disorder caused by factor VIII (F8) deficiency. F8 rearrangements involving intron 22 (int22) and intron 1 (int1) account for almost half of severe HA phenotype also a hotspot exon 14 provides numerous mutational patterns. This study aims to identify F8 gene mutations among Egyptian HA patients.
DNA samples from 60 HA patients were screened for int22 and int1 rearrangements using simplified inverse shifting PCR (IS-PCR) followed by exon 14 sequencing. Also, four uncharacterized patients were studied by targeted exome sequencing.
In 33.3% of the studied patients, we identified three int22 rearrangements, three exon 14 mutations (two frameshift; one novel (NM_000132.3:c.2734_2735delAA, p.(N912Ffs6)), a second reported mutation (NM_000132.3:c.3091_3094delAGAA, p.(K1031Lfs9)), and one nonsense mutation (NM_000132.3:c.2440C>T, p.(R814*)). All identified mutations were detected in patients with severe HA phenotype. Targeted exome sequencing could not detect any known pathogenic variants.
Intron 22 rearrangement and exon 14 mutations correlate with most severe hemophilia A Egyptian patients.
血友病 A (HA) 是一种由凝血因子 VIII (F8) 缺乏引起的遗传性 X 连锁隐性凝血障碍。F8 基因内含子 22 (int22) 和内含子 1 (int1) 的重排几乎占严重 HA 表型的一半，也是热点外显子 14 提供了许多突变模式。本研究旨在鉴定埃及 HA 患者的 F8 基因突变。
使用简化反向移位 PCR (IS-PCR) 筛选 60 名 HA 患者的 DNA 样本，以检测 int22 和 int1 重排，随后对外显子 14 进行测序。此外，还对四名未明确的患者进行了靶向外显子组测序。
在所研究的患者中，我们发现了 33.3%的患者存在三种 int22 重排、三种外显子 14 突变（两种移码；一种新的 (NM_000132.3:c.2734_2735delAA, p.(N912Ffs6)），第二种报道的突变 (NM_000132.3:c.3091_3094delAGAA, p.(K1031Lfs9)) 和一种无义突变 (NM_000132.3:c.2440C>T, p.(R814*)))。所有鉴定的突变均在严重 HA 表型的患者中检测到。靶向外显子组测序未能检测到任何已知的致病性变异。
内含子 22 重排和外显子 14 突变与大多数严重的埃及血友病 A 患者相关。
