developmental patterning
Patterning of the vertebrate embryo occurs with respect to three body axes.
Prior to the left-right axis (L-R axis), the anterio-posterior axis (A-P axis) and dorso-ventral axis (D-V axis) are formed. These two body axes automatically define the left and the right side of the embryo that initially shows bilateral symmetry.
Starting from an embryo with two body axes and bilateral symmetry, the development of morphological Left-Right asymmetry can be divided into three phases:
1. Breaking of global embryonic bilateral symmetry and stabilizing this information in an organizing center.
2. left-right information is propagated and transmitted to more outlying tissue and a cascade of asymmetric gene expression is triggered.
3. Recognition of the left-right information by organ primordia and the translation into asymmetric organ morphology.
Types
rostral-caudal patterning
anterior patterning
skeletal patterning
Pathology
patterning disorders
References
Morgan R. Hox genes: a continuation of embryonic patterning? Trends Genet. 2006 Feb;22(2):67-9. PMID: #16325300#
Serra R, Chang C. TGF-beta signaling in human skeletal and patterning disorders. Birth Defects Res Part C Embryo Today. 2003 Nov;69(4):333-51. PMID: #14745974#