Kirkuk University Journal for Agricultural Sciences (KUJAS)

The Relationship Between BDNF Copy Number Variation and Humoral Immunity in Awassi Sheep: a Molecular–Immunological Study

https://doi.org/10.58928/ku26.17206
Volume 17, Issue 2
Spring 2026
Page 47-56
Kirkuk University Journal for Agricultural Sciences (KUJAS)

Document Type : Research Paper

Authors

Hamzah Riyadh Abdulhameed 1
Dhiaa Sabah Ibrahim 2
Khaleel Ibrahem Jawasreh 3

1 Department of Chemistry, College of Education for Pure Sciences, University of Samarra, IRAQ.

2 Department of Biology, College of Education for Pure Sciences, University of Samarra, IRAQ.

3 Department of Animal Production, Faculty of Agriculture, Jordan University of Science and Technology, Jordan

Abstract
Humoral immunity (Secretory IgA (SIgA), IgM, IgG) and copy number variation (CNV) of BDNF gene and its expression were assessed in Awassi sheep blood samples (n = 40). CNV analysis were performed via qPCR (ΔΔCt method), BDNF gene expression analysis through SYBR Green qPCR, and IgA, IgM and IgG ELISA were used to determine serum immunoglobulin levels.ANOVA followed by Duncan’s test was used to compare differences among deletion (DEL), normal CNV (NOR) and duplication (DUP) groups and Pearson and Spearman correlations were used to determine linear and monotonic relationships. IgM and IgG serum levels were not significantly different among CNV groups and had no significant correlations with BDNF CNV coding respectively (P > 0.05). However, serum levels of IgA had a significant group effect (P ≤ 0.05). Normal CNV group had higher levels of IgA compared to DEL and DUP groups. Similarly, BDNF gene expression was significantly higher in the NOR group compared to DEL and DUP groups showing a clear dose response relationship indicating gene dosage sensitivity and nonlinear response to CNV. Pearson correlation coefficient between IgA and CNV coding was not significant (p > 0.05), however Spearman correlation rho value approached significance showing a positive monotonic association (rho = 0.305, P = 0.056). Both analyses suggest a relationship between IgA and CNV dosage that may become significant with increased sample size. Taken together our results indicate BDNF requires an optimal dosage range and BDNF-associated neuroimmune communication may contribute to mucosal immune response with IgA being the immunoglobulin most likely to reflect these changes.

Keywords

BDNF Gene
Copy Number Variation (CNV)
Humoral immunity
Gene Dosage Sensitivity
Sheep
Awassi
Subjects
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