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.