For example, a 247 nucleotide (nt) transcript 1Kb upstream of the transcription start site of Adamst6, a member of a thrombospondin-like metalloproteinase family implicated in Weill-Marchesani Syndrome (WMS–which features cardiac fibrosis as a component of its pathogenic sequelae) [31] and congenital heart disease (CHD) [32], was upregulated in both d8 and CLK CPCs and appeared to generally correlate positively with Adamts6 expression levels, as its absence in undifferentiated ES cells was also concomitant with a lack of Adamts6 expression (Fig 4A). Here, ADAMTS6 is linked to Weill-Marchesani syndrome.