Beta thalassemia syndromes: New insights

Table 1 Beta thalassemia variants

Type of β-globin gene variant		Subtype of β-globin gene variant	Beta-thalassemia severity type
Point mutations	Trancriptional variants	Promoter regulatory elements; 5’ untranslated regions	β+ or β++
	Variants involving RNA processing	Splice junction; consensus splice sites; cryptic splice sites; RNA cleavage - poly A signal; others in 3’ untranslated regions	β0, β+ or β++
	Variants involving RNA translation	Initiation codon; nonsense codons; frameshift	β0
Deletions			β0