[Neonatal screening of hemoglobinopathies and G6PD deficiency in Catalonia (Spain). Molecular study of sickle cell disease associated with alpha thalassemia and G6PD deficiency].
OBJECTIVE
The prevalence of hemoglobinopathies and glucose-6-phosphate dehidrogenase (G6PD) deficiency in the Catalan neonatal population is increasing due to immigration. Coinheritance of more than a single RBC genetic defect is becoming more frequent and diagnostic pitfalls are also increasing. We intended to demonstrate the need to perform an early diagnosis of sickle cell disease (SCD) by means of neonatal screening, to establish the prevalence of SCD associated with alpha thalassemia and G6PD deficiency and to identify genotypes associated with sickle cell disease and G6PD deficiency.


METHODS
4,020 blood samples from newborns were screened. For the screening of hemoglobinopathies the high performance liquid chromatography method was used and for G6PD deficiency the fluorescent spot test was employed. We studied the association between betaS gene and alpha thalassaemia del-3.7 Kb. SCD and G6PD deficiency genotypes were established.


RESULTS
Prevalence of SCD in population at risk was 1/475 newborns. Prevalence of G6PD deficiency in population at risk was 1/43, and in autochthonous population was 1/527 newborns. In all the cases, sickle hemoglobin was confirmed by ARMS (amplification refractory mutation system). Association between betaS gene and alpha thalassaemia del-3.7 Kb was found in 32.2% of the samples, and an association between betaS gene and G6PD deficiency was observed in 7% of the samples.


CONCLUSIONS
This study confirms the high prevalence of SCD and G6PD deficiency in population at risk as well as their genetic and clinical heterogeneity. The study of genotype/phenotype relationships allows a better knowledge of molecular mechanism and is useful to establish suitable criteria of diagnosis.
Unidad de Eritropatología, Hospital Clínic i Provincial de Barcelona, Barcelona, España. mdmanupe7@bio.ub.edu
María Del Mar
Mdel M
Mañú Pereira
Anna
A
Cabot
Ana
A
Martínez González
Eulalia
E
Sitjà Navarro
Vicent
V
Cararach
Josep
J
Sabrià
Jordi
J
Boixaderas
Roser
R
Teixidor
Albert
A
Bosch
M Angeles
MA
López Vílchez
Itziar
I
Martín Ibáñez
Teresa
T
Carrión
Pere
P
Plaja
Mario
M
Sánchez
José Luis
JL
Vives Corrons
D000755:Anemia, Sickle Cell / Q000097:blood / Q000175:diagnosis*; D005260:Female; D005312:Fetal Blood; D005955:Glucosephosphate Dehydrogenase Deficiency / Q000097:blood / Q000175:diagnosis*; D006453:Hemoglobinopathies / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D015997:Neonatal Screening; D013030:Spain; D017085:alpha-Thalassemia / Q000097:blood / Q000175:diagnosis*