LZTR1 and Noonan syndrome: Regarding genes causing syndromes with a risk of ALL, we found two P/LP variants in Li-Fraumeni and Noonan syndrome -causing genes: one P variant in TP53 (p.Gly245Ser) and one in LZTR1 (c.2407-1G > A) (Fig. 1a, Table 2).