HEY1 and nail-patella syndrome: Concerning the expression of Notch target genes, we found that HEY1 was upregulated in NP from four of 10 patients and downregulated in NP of three of 10 patients, compared to the corresponding A,M whereas in the remaining three patients there was no difference in its expression level between NP and AM (Figure 1c); HEY2 resulted upregulated in NPs of three of 10 patients, downregulated in NP of two patients and in the remaining five patients there was no difference between NP and AM (Figure 1c).