TMEM165 and congenital disorder of glycosylation: A second, the human transmembrane protein 165 (TMEM165), attracted much interest when its involvement in the rare condition known as congenital disorders of glycosylation (CDG) was demonstrated in 2012 (Foulquier et al., 2012; Rosnoblet et al., 2013; Zeevaert et al., 2013; Bammens et al., 2015; Potelle et al., 2016; Schulte Althoff et al., 2016; Krzewinski-Recchi et al., 2017; Morelle et al., 2017).