The signs and symptoms of Warsaw breakage syndrome include:[3][4] The Israeli Health Ministry describes the condition manifestation as "characterized by smaller than average head circumference (microcephaly) as early as the embryonic stage, intrauterine growth restriction (IUGR) as well as postnatal growth restriction (dwarfism).
[4][6] DDX11 mutation that causes WABS is described at US National Library of Medicine:[7] The DDX11 gene provides instructions for making an enzyme called ChlR1.
In addition, after DNA is copied, ChlR1 plays a role in ensuring proper separation of each chromosome during cell division.
DDX11 gene mutations severely reduce or completely eliminate ChlR1 enzyme activity.
A lack of functional ChlR1 impairs cell division and leads to an accumulation of DNA damage.