A novel HBA2 gene conversion in cis or trans: "α12 allele" in a Saudi population.
PMID 25065854 | DOI 10.1016/j.bcmd.2014.07.001 · Blood cells, molecules & diseases · 2014 · View on PubMed ↗
Thalassemia and sickle cell disease are the most prevalent hemoglobin disorders in the populations of Dammam, Al-Qatif and Al-Ahsa regions in the Eastern Province of Saudi Arabia where our study cases originated. Increased HbF can modify these disorders. Direct sequencing of the HBA2 and HBA1 genes from 157 Saudi subjects revealed a new HBA2 gene conversion in cis or trans in 5.7% of the total. We refer to this new HBA2 gene convert as an α12 (HBA12) allele due to its combination of α1 (HBA1) and α2 (HBA2) sequences. Three genotypes, homozygous (-α12(3.7)/α1α12), heterozygous (α1α2/α1α12) and hemizygous (α1- (4.2)/α1α12) for the α12 allele were observed. The majority of individuals who were positive for the α12 allele had a reduction in the percentage of HbA2. Further studies are necessary to evaluate the possible effect of these changes on globin gene expression.
Validated evidence
| Type | Entity | Source evidence | Confidence | Extractor |
|---|---|---|---|---|
| gene | HBA2 | “A novel HBA2 gene conversion in cis or trans: "α12 allele" in a Saudi population.” | 0.98 | hgnc_dict_v1 |
| gene | HBA1 | “Direct sequencing of the HBA2 and HBA1 genes from 157 Saudi subjects revealed a new HBA2 gene conversion in cis or trans in 5.7% of the total.” | 0.98 | hgnc_dict_v1 |
| phenotype | sickle cell disease | “Thalassemia and sickle cell disease are the most prevalent hemoglobin disorders in the populations of Dammam, Al-Qatif and Al-Ahsa regions in the Eastern Province of Saudi Arabia where our study cases originated.” | 0.98 | phenotype_alias_lexicon_v2 |
| phenotype | thalassemia | “Thalassemia and sickle cell disease are the most prevalent hemoglobin disorders in the populations of Dammam, Al-Qatif and Al-Ahsa regions in the Eastern Province of Saudi Arabia where our study cases originated.” | 0.98 | phenotype_alias_lexicon_v2 |
| population | Saudi Arabia, Eastern Province | “A novel HBA2 gene conversion in cis or trans: "α12 allele" in a Saudi population. Thalassemia and sickle cell disease are the most prevalent hemoglobin disorders in the populations of Dammam, Al-Qatif and Al-Ahsa regions in the Eastern Province of Saudi Arabia where our study cases originated. Direct sequencing of the HBA2 and HBA1 genes from 157 Saudi subjects revealed a new HBA2 gene conversion in cis or trans in 5.7% of the total.” | 0.95 | saudi_context_rules_v1 |