A new alpha(0)-thalassemia deletion found in a Dutch family (--(AW)).
Alpha-thalassemia is an inherited hemoglobin disorder characterized by a microcytic hypochromic anemia caused by a quantitative reduction of the alpha-globin chain. The majority of the alpha-thalassemias is caused by deletions in the alpha-globin gene cluster. A deletion in the alpha-globin gene cluster, which was found in a Dutch family, was characterized by MLPA, long-range PCR and direct sequencing. We describe the molecular characterization of a novel 8.2kb deletion (--(AW)), involving both alpha-globin genes in cis. The deletion is caused by a non-homologous recombination event between an Alu and an L1-repeat sequence. This deletion is the third example of a non-homologous recombination event involving an Alu and an L1 repeat, and the first described in the human alpha-globin gene cluster. Because of a 25% risk of Hb Bart's with hydrops foetalis in the offspring when in combination with another alpha(0)-thalassemia allele, it is important to diagnose this deletion.
Phylipsen
Marion
M
Department of Human and Clinical Genetics, Leiden University Medical Center, The Netherlands. m.phylipsen@lumc.nl
Vogelaar
Ingrid P
IP
Schaap
Rianne A C
RA
Arkesteijn
Sandra G J
SG
Boxma
George L
GL
van Helden
Willem C H
WC
Wildschut
Irene C M
IC
de Bruin-Roest
Andrea C
AC
Giordano
Piero C
PC
Harteveld
Cornelis L
CL
D000328:Adult; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D017384:Sequence Deletion / Q000235:genetics*; D055542:alpha-Globins / Q000172:deficiency* / Q000235:genetics*; D017085:alpha-Thalassemia / Q000097:blood / Q000175:diagnosis / Q000235:genetics*
D055542:alpha-Globins