TG and congenital hypothyroidism: In agreement with observations in children with congenital hypothyroidism (Gupta et al., 1995), these findings suggest that thyroid hormone may be less important for the start of the myelination process, but very relevant for normal maturation, as evidenced by the number of differentially expressed genes and the clearly distinct UMAP embeddings between the oligodendrocytes from wild-type and TRα1+m mice.