Imputing single-cell RNA-seq data by graph autoencoder with multi-kernel

Single-cell RNA-sequencing (scRNA-seq) technology has revolutionized the field by enabling the profiling of transcriptomes in cell resolution. However, it is flawed by the sparsity caused by low mRNA capture efficiency during sequencing. This results in "dropout" events where genes are expressed but not detected. Dropout can hinder downstream analyses like differential expression and clustering. To tackle this issue, we present a novel imputation approach called MKGAE, which utilizes graph convolution and autoencoder techniques to construct a generative model for imputing missing values within scRNA-seq data. Meanwhile, considering the intricate relationships between genes, merging them into a single graph might lead to the loss of important insights. To address this, we utilize two gene-to-gene graph kernels for graph convolution. Experiments across both simulated and real scRNA-seq datasets illustrate MKGAE's superiority over other state-of-the-art methods in terms of clustering analysis and differentially expressed gene identification.