Correction to: Rapid and reliable detection of α-globin copy number variations by quantitative real-time PCR.

[This corrects the article DOI: 10.1186/2052-1839-14-4.].

Correction to: BMC Hematol (2014) 14:4

https://doi.org/10.1186/2052-1839-14-4

The copy number of the HBA1 assay for the -(α)20.5 deletion in the HBA-CNV method described in the original article [1] was incorrectly reported. The authors wish to note that the HBA1 assay will not be affected by the –(α)20.5 deletion and will show two copies (Table 1 - corrected). The 3′ breakpoint of the –(α)20.5 deletion is located within exon 2 of the HBA1 gene [2], leaving intact the area where the HBA1 assay is amplifying. The partial deletion of HBA1 causes a complete abolition of the gene expression, hence –(α)20.5 is considered as a double gene deletion. This shows that even though the HBA1 assay may show two copies, a deletion affecting both alpha-globin genes can not be excluded. Similarly, the Hb Var database contains examples of deletions that will not influence HBA2 assay copy number despite affecting both alpha-globin genes. Hence, molecular data should always be evaluated together with hematological data.

Table 1

Predicted copy number in 108 patient samples

Genotype	Samples (n)	Copy Number Predicted
		HBA1	HBA3.7	HBA2	HS-40
αα/αα	63	2	2	2	2
-α3.7/αα	22	2	1	2	2
-α4.2/αα	2	2	2	1	2
-α3.7/-α3.7	8	2	0	2	2
--SEA/αα	7	1	1	1	2
--FIL/αα	1	1	1	1	2
-(α)20.5/αα	1	2	1	1	2
--MED/αα	1	1	1	1	2
-α3.7/--SEA	1	1	0	1	2
αα/αααanti3.7	2	2	3	2	2
Total	108