Abstract
Introduction: Down syndrome is are three chromosome copies (trisomy) from chromosome 21 in the somatic cells of a person. People may have Mosaic Down syndrome, which is a combination of two types of cells, meaning that they are two cell lines of one fertilized cell (zygote). Some cells contain 46 chromosomes, indicating that they are normal cells, while other cells contain 47 chromosomes; cells with 47 chromosomes contain an extra chromosome 21. Objective: The relationship between Mosaic Down syndrome and thyroid gland shape and between Mosaic Down syndrome and thyroid gland hormones T3, T4 and TSH, and effect of honey on those with hypothyroidism. Methods: This cross-sectional study included 20 boys aged 10 years with mosaic Down syndrome and 6 controls. Karyotyping and thyroid hormone measurements were performed, and the effect of honey on thyroid hormone concentrations was evaluated. The study was approved by University of Baghdad Institutional Review Board, Baghdad, Iraq (reference No. 0854; 22 March 2025). Written informed consent was obtained from the parents or legal guardians of all participating children, and age-appropriate assent was obtained from the children before sample collection and study procedures. Results: The highest percentage of thyroid hormones (57, 0.75, 0.35), (T3, T4, TSH) in the sample in which the lowest percentage of mosaicism was 8.16%, and the lowest percentage of thyroid hormones was recorded (9, 0.01, undetectable), (T3, T4, TSH) in the sample that had the highest percentage of mosaicism (32.25%). The rate of decrease in thyroid hormone levels increases further as the percentage of mosaicism increases, the percentage of sister chromatids exchanged in the group with mosaic Down syndrome was (62.46 ±6.12) compared to the percentage of exchanges in the control group (41.61 ± 4.84), honey was highly effective in raising thyroid hormone levels. Conclusion: All patients with Mosaic Down syndrome have hypothyroidism, and the rate of decline in thyroid hormones increases further as the percentage of mosaicism increases, the higher the degree of mosaicism, the greater the rate of sister chromatid exchange, there were significant differences; honey raised the level of thyroid hormones in patients.