Abstract
The gut flora is thought to be critical to the development of the brain, and the role of the “gut-brain axis” in cognition has been gradually confirmed in recent years. Our previous studies have shown that there are significant differences in gut bacteria flora between children with Down syndrome (DS) and normal children. Compared with the gut bacteria flora, there are few studies on the gut fungi flora in DS. Although the abundance of fungi in the gut is relatively low, the imbalance of fungal flora also plays a very important role in the occurrence and development of diseases, changing before the appearance of early symptoms of diseases, through direct action or interaction with gut bacteria. In this study, the characterization of gut fungal and bacterial flora of children with DS from different provinces of China were simultaneously conducted via 16S and ITS sequencing. The results clearly showed dysbiosis of the gut flora in DS, andthere were differences in the gut flora related to the nervous system, such as Faecalibacterium, Prevotella, Clostridiales and Candida, which could ultimately affect cognitive function. In addition, this study further indicated changes in interactions between Candida and other gut flora in children with DS, which has proved to be a main pathogen of nerve damage in the brain. This work revealed the dysbiosis in DS gut flora and the relationship of them was analyzed, which may provide a new theoretical support for the pathogenesis of DS and other related cognitive disorders.