Table 9.

Noonan Syndrome: Mechanism of Disease Causation

Gene 1MechanismComment/Reference
BRAF Gain of
function		 Sarkozy et al [2009]
KRAS
LZTR1 Gain of
function		For heterozygous pathogenic variants that lead to autosomal dominant LZTR1-related Noonan syndrome [Motta et al 2019]
Loss of
function		Recessive variants typically influence protein synthesis/stability or subcellular localization [Motta et al 2019].
MAP2K1 Gain of
function		Cirstea et al [2010], Runtuwene et al [2011]
MRAS Higgins et al [2017], Motta et al [2020]
NRAS
PTPN11
RAF1 Pandit et al [2007]
RASA2 Chen et al [2014b]
RIT1 Aoki et al [2013]
RRAS Chen et al [2014b], Flex et al [2014]
SOS1 Roberts et al [2007]
SOS2 Chen et al [2014b], Yamamoto et al [2015], Lissewski et al [2021]
1.

Genes from Table 1 in alphabetic order

From: Noonan Syndrome

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