Galnt18, a gene of significance, is involved in the mucin-type glycosylation process within the Golgi apparatus [3]. When there is mucin-type Golgi stress, the expression of Galnt18 is increased as part of a novel response pathway that enhances the expression of glycosylation enzymes for mucins, and it also seems to be related to the crosstalk between the mucin pathway and the TFE3 pathway [3].

In human studies, the GALNT18-CC genotype was associated with a better EULAR response, remission, and DAS28 improvement in rheumatoid arthritis patients treated with tocilizumab [1]. Also, the C-allele of GALNT18 was an independent factor capable of predicting higher LDA rates at 6 and 18 months in these patients [1]. Additionally, in Chinese children, the rs274503 polymorphism in ZBED5/GALNT18 was associated with the risk of idiopathic clubfoot, with the G allele increasing the risk, especially in bilateral cases [2]. Moreover, in lupus patients, demethylation of a CpG site within GALNT18 was associated with the development of active lupus nephritis [4]. In Chinese rheumatoid arthritis patients, GALNT18 rs4910008 was significantly associated with CDAI LDA [5]. In dairy cattle, GALNT18 was among the genes identified within differential CNVRs potentially associated with milk protein and fat traits [6].

In conclusion, Galnt18 is crucial in mucin-type glycosylation and the Golgi stress response. Its genetic variations are associated with various diseases such as rheumatoid arthritis, idiopathic clubfoot, and lupus nephritis. These findings from human and animal studies highlight its importance in understanding disease mechanisms and potentially developing targeted therapies.