Contributions
Abstract: PB2408
Type: Publication Only
Background
: Sickle cell disease (SCD) is an inherited disease associated with the chronic inflammatory condition indicated by elevated levels of inflammatory cytokines and increased Th17 response. These inflammatory pathways may be directly regulated by genetic polymorphisms and could be associated with different outcomes of the disease. Interleukin-4 (IL-4) is the main cytokine of T helper 2 lymphocytes, which has a key role in the regulation of humoral immune responses. The expression level of IL-4 gene could change by the 70 bp variable number of tandem repeat (VNTR) polymorphism that found in its third intron. In Africa (SCD) is one of the most common inherited disorders of hemoglobin and varies in frequency between different areas in Sudan.
Aims
The aim of this study was to detect the distribution of IL-4(VNTR) alleles among Sudanese patients with SCA and to investigate the possible associations with the development of stroke among these patients.
Methods
One hundred patients (50 male and 50 female; 8.34 ± 6.67 years) with SCD and one hundred (47 male and 53 female; 8.64±4.99 years) healthy blood donors were evaluated. The polymorphisms were performed by PCR analysis and described as genotype frequencies.
Results
The entire RP1/RP2 genotype carriers were SCD patients. A significant difference in the distribution of RP2/RP2 genotype was found among patients (16%) and controls (41%) (P =0. 000) and it was only found among western Sudan tribes .RP1/RP1 genotype frequency was almost the same between (patients: controls), (53%: 59%). RP1 allele can be considered as risk factor for SCD as it was found 1.5 fold time to be in SCD patients than in controls (O.R =1.51)
Table: IL-4 VNTR genotypes and alleles distributions among SCD patients and controls.
Genotype | Patients N (%)
| Control N (%)
| P-value | OR(95% CI) |
RP1/RP1
| 53(53.0) | 59(59.0)
| 0.393
| 0.78(0.48 - 1.37) |
RP1/RP2
| 31(31.0)
| 0
| 0.000**
| -
|
RP2/RP2
| 16(16.0) | 41(41.0) | 0.000**
| 0.27(0.14 - 0.53) |
Alleles RP1
Alleles RP2 | 137(68.5)
118(59.0) | 63(31.5)
82(41.0) | 0.048* | 1.511(1.002 - 2.278) |
* P-value<0.05 statistical significantly **P-value<0.001 highly significantly different, OR=Odd Ratio, CI= Confident interval
Conclusion
Summary: In this study, there were three main genotypes of IL-4 identified (RP1/RP1, RP1/RP2, RP2/RP2) in the patients and controls. The risk of sickle cell patients was higher in individuals with RP1/RP2 genotype than controls. In addition, the frequency of allele 1 was higher in sickle cell anemia patients (68.5%), but this difference was weak evidence, therefore, this allele could be a risk factor for sickle cell patients (O.R =1.5).The distribution of SCD among Sudanese population directly affect the frequency of IL4 VNTR among different tribes. Studies in Sudan reported the presence of SCD in western tribes mainly.
CONCLUSIN: The RP1 allele could be a risk factor for sickle cell anemia patients. No statistically significant difference between tribes in VNTR allele's distribution, but Darfour and Kordofan tribes showed high frequency of RP2 allele.
Session topic: 27. Sickle cell disease
Keyword(s): Polymorphism, sickle cell disease
Abstract: PB2408
Type: Publication Only
Background
: Sickle cell disease (SCD) is an inherited disease associated with the chronic inflammatory condition indicated by elevated levels of inflammatory cytokines and increased Th17 response. These inflammatory pathways may be directly regulated by genetic polymorphisms and could be associated with different outcomes of the disease. Interleukin-4 (IL-4) is the main cytokine of T helper 2 lymphocytes, which has a key role in the regulation of humoral immune responses. The expression level of IL-4 gene could change by the 70 bp variable number of tandem repeat (VNTR) polymorphism that found in its third intron. In Africa (SCD) is one of the most common inherited disorders of hemoglobin and varies in frequency between different areas in Sudan.
Aims
The aim of this study was to detect the distribution of IL-4(VNTR) alleles among Sudanese patients with SCA and to investigate the possible associations with the development of stroke among these patients.
Methods
One hundred patients (50 male and 50 female; 8.34 ± 6.67 years) with SCD and one hundred (47 male and 53 female; 8.64±4.99 years) healthy blood donors were evaluated. The polymorphisms were performed by PCR analysis and described as genotype frequencies.
Results
The entire RP1/RP2 genotype carriers were SCD patients. A significant difference in the distribution of RP2/RP2 genotype was found among patients (16%) and controls (41%) (P =0. 000) and it was only found among western Sudan tribes .RP1/RP1 genotype frequency was almost the same between (patients: controls), (53%: 59%). RP1 allele can be considered as risk factor for SCD as it was found 1.5 fold time to be in SCD patients than in controls (O.R =1.51)
Table: IL-4 VNTR genotypes and alleles distributions among SCD patients and controls.
Genotype | Patients N (%)
| Control N (%)
| P-value | OR(95% CI) |
RP1/RP1
| 53(53.0) | 59(59.0)
| 0.393
| 0.78(0.48 - 1.37) |
RP1/RP2
| 31(31.0)
| 0
| 0.000**
| -
|
RP2/RP2
| 16(16.0) | 41(41.0) | 0.000**
| 0.27(0.14 - 0.53) |
Alleles RP1
Alleles RP2 | 137(68.5)
118(59.0) | 63(31.5)
82(41.0) | 0.048* | 1.511(1.002 - 2.278) |
* P-value<0.05 statistical significantly **P-value<0.001 highly significantly different, OR=Odd Ratio, CI= Confident interval
Conclusion
Summary: In this study, there were three main genotypes of IL-4 identified (RP1/RP1, RP1/RP2, RP2/RP2) in the patients and controls. The risk of sickle cell patients was higher in individuals with RP1/RP2 genotype than controls. In addition, the frequency of allele 1 was higher in sickle cell anemia patients (68.5%), but this difference was weak evidence, therefore, this allele could be a risk factor for sickle cell patients (O.R =1.5).The distribution of SCD among Sudanese population directly affect the frequency of IL4 VNTR among different tribes. Studies in Sudan reported the presence of SCD in western tribes mainly.
CONCLUSIN: The RP1 allele could be a risk factor for sickle cell anemia patients. No statistically significant difference between tribes in VNTR allele's distribution, but Darfour and Kordofan tribes showed high frequency of RP2 allele.
Session topic: 27. Sickle cell disease
Keyword(s): Polymorphism, sickle cell disease