Table 1. Characteristic features of ptpn11a-/-, ptpn11b -/- and double mutant embryos.

Characteristics	ptpn11a-/-	ptpn11b-/-	ptpn11a-/-ptpn11b-/-
Head	Reduced in some cases	Normal	Enlarged by edema. Prominent jaw
Heart	Normal	Normal	Severe edema
Swim bladder	Absent	Normal	Absent
Length	Shorter	Normal	Shorter
Ventral region	Reduced, skinny appearance	Normal	Grossly edematous. Reduced organs.