Detection of IL-4
proximal promoter mutation of asthmatic patients and preliminary analysis
Zhou
YF, Li CR, Wu JM, Lam Wk
1 Shenzhen Children��s Hospital,
Shenzhen, China
2 Molecular Biological Laboratory
of Union Hospital of Tongji Medical University
3 Department of Chemical Pathology,
Chinese University of Hong Kong, Hong Kong
Objective: To clone and detect mutation sites within interleukin-4 (IL-4)
promoter of asthmatic patients.
Methods: The IL-4 proximal promoter segments were obtained by Polymerase
chain reaction (PCR) with genomic DNA as template .Four patients�� samples
were selected from thirty asthmatic patients and twenty healthy children
through PCR and single strand conformation polymorphysim��PCR-SSCP��. The PCR segments of the four
patients were cloned into plasmids JX2. The PCR inserts were sequenced by
dideoxy chain termination method in the end.
Results: The IL-4 proximal promoter sequences of the normal child were
the same as the sequences of the gene pool. Some new potential important sites
were found: (1) A C to A transversion located at -229 position was just
within PRE-I element in one patient. (2) A C to T transition adjacent to
NRE-II elements and an extra G adjacent to TATA box were found in two
patients. (3) A five bases nucleotide deletion was found near STAT-6 RE
element in one patient.
Conclusion: Multiple allelic forms of the human IL-4 promoter do exist
within asthmatic patients. These polymorphism sites might result in
aberrant expression of IL-4 gene.