First case of Hb Fontainebleau with sickle haemoglobin and other non-deletional α gene variants identified in neonates during newborn screening for sickle cell disorders

Abstract

Newborn screening for sickle cell disorders also enabled us to identify three α globin chain variants. Two babies who inherited Hb Fontainebleau and Hb O Indonesia along with Hb S had reduced Hb levels at birth and need to be followed up.

A novel double heterozygous Hb Fontainebleau/HbD Punjab hemoglobinopathy

“…Molecular testing revealed co-inheritance of Hb Fontainebleau with HbD-Punjab, a novel double heterozygous hemoglobinopathy. Although Hb Fontainebleau has previously been reported in association with HbS [10], to the best of our knowledge, this is the first report of Hb Fontainebleau in association with HbD-Punjab.…”

“…Analysis by a second method based on a different analytical principle follows the recommendations of the British Committee for Standards in Haematology [9][10][11]. Definite diagnosis, however, can only be obtained by DNA sequencing analysis.…”

“…HbD-Punjab was the third most common β-\chain variant found in our Northern Alberta population in 2013 [9]. The only double heterozygous hemoglobinopathy described to date involving Hb Fontainebleau is Hb Fontainebleau/HbS which was found during a neonatal screening program [10].…”

Haemoglobin Fontainebleau (HBA2: c. 64G>C) in Oman: molecular and haematological characteristics and interaction with various haemoglobinopathies

“…Hb FB has been described as occurring with Hb S,12 Hb D-Punjab13 and iron deficiency anaemia 14. We have found similar interactions in our population.…”

Newborn screening for haemoglobinopathies by high performance liquid chromatography (HPLC): diagnostic utility of different approaches in resource-poor settings

“…Three non-deletional α haemoglobin variants (Hb Fontainebleau, HbO Indonesia and Hb Koya Dora) were also picked up by the β-thal short kit and cellulose acetate electrophoresis in newborns [25]. These cases were diagnosed on the basis of the presence of a peak in an unknown window (HbO Indonesia and Hb Fontainebleau) and an abnormally shaped peak (Hb Fontainebleau) and the presence of a spike on HPLC using the β-thal short kit (Hb Koya Dora) compared to the sickle cell short kit which only gave the percentage of fast peaks and in one case an unknown window (HbO Indonesia) thereby making it difficult to pick up the non-deletional α gene variants ( Table 2) [25]. One case of haemoglobin H (HbH) was also picked up using the β-thal short kit on the basis of the presence of a spike and two fast moving bands on cellulose acetate electrophoresis (unpublished data).…”