Nonhomologous recombination between the cytochrome b558 heavy chain gene (CYBB) and LINE-1 causes an X-linked chronic granulomatous disease.
We cloned and characterized a genomic DNA fragment including the deletion junction of a chronic granulomatous disease patient with a 25-kb deletion extending to the 5' two-thirds of CYBB. The 3' breakpoint of the deletion exists in exon 7 of CYBB. A LINE-1 element lies at 5 kb upstream of CYBB in normal persons, and the 5' breakpoint of the deletion in the patient is in the LINE-1 element. There are no significant homologies between corresponding normal 5' and 3' regions flanking the breakpoint of the patient, so a nonhomologous recombination is the most possible mechanism for this 25-kb deletion. The analysis also reveals that the patient has a novel 30-bp duplication in the 5' flanking region of the deletion point, which was transmitted by his mother with the deletion. Furthermore we suggest that the deletion occurred in his grandfather.
Kumatori
A
A
Institute of Tropical Medicine, Nagasaki University, Nagasaki, 852-8523, Japan. kumatori@net.nagasaki-u.ac.jp
Faizunnessa
N N
NN
Suzuki
S
S
Moriuchi
T
T
Kurozumi
H
H
Nakamura
M
M
D001483:Base Sequence; D015139:Blotting, Southern; D003573:Cytochrome b Group / Q000235:genetics*; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics / Q000378:metabolism; D005260:Female; D006105:Granulomatous Disease, Chronic / Q000235:genetics*; D006801:Humans; D020071:Interspersed Repetitive Sequences; D008297:Male; D008969:Molecular Sequence Data; D019255:NADPH Oxidases; D010375:Pedigree; D011110:Polymorphism, Genetic; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D014960:X Chromosome
D003573:Cytochrome b Group; C036888:cytochrome b558; D019255:NADPH Oxidases; D015252:Deoxyribonucleases, Type II Site-Specific