Beta-chain variants in Jamaican newborns

Area of Science:

• Hematology
• Genetics
• Molecular Biology

Background:

• Hemoglobinopathies are common genetic disorders globally.
• Beta-chain hemoglobin variants, including sickle cell disease (Hb S) and Hemoglobin C (Hb C), have significant public health implications.
• Understanding the prevalence of these variants is crucial for genetic counseling and public health initiatives.

Purpose of the Study:

• To investigate the prevalence of beta-chain hemoglobin variants in a Jamaican population.
• To identify and characterize rare beta-chain hemoglobin variants.
• To determine the frequencies of common beta-chain variants (Hb S and Hb C).

Main Methods:

• Electrophoretic analysis of 15,661 Jamaican cord blood samples.
• Identification and characterization of beta-chain hemoglobin variants.
• Calculation of heterozygote frequencies for common and rare variants.

Main Results:

• Eight rare beta-chain variants were identified in 18 subjects.
• The heterozygote frequencies for Hb S and Hb C were 10.1% and 3.7%, respectively.
• Hb Korle Bu (7 cases) and Hb O su-Christiansborg (3 cases) were the most frequent rare variants. A novel variant, Hb Caribbean (beta 91 Leu leads to Arg), was discovered.

Conclusions:

• The study provides valuable data on the spectrum and frequency of beta-chain hemoglobin variants in Jamaica.
• The identification of a new variant, Hb Caribbean, expands the known diversity of beta-chain hemoglobinopathies.
• These findings underscore the importance of newborn screening and genetic counseling for hemoglobinopathies in the region.