A reexamination of two skeletal mutants of the mouse, vestigial tail (vt) and congenital hydrocephalus (ch)

Abstract

The development of 2 skeletal mutants in the mouse was reinvestigated. In vestigial tail (vt), a simple syndrome is traceable to an anomaly of the primitive streak. In congenital hydrocephalus (ch), the complicated events were followed to a level at which the most fundamental gene action detected (or, more accurately, postulated) is no longer demonstrable by conventional histological methods. It involves the mesenchyme and some of its direct derivatives (meninges, skeletal blastemata, mesonephros), but also organs of different origin (nasal glands, ureteric bud, certain ganglia) for which the mesenchyme is the environment. Failure of the meningeal mesenchyme to form the subarachnoid drainage system for the cerebrospinal fluid leads to hydrocephalus which, by essentially mechanical means, is responsible for a multitude of subordinated effects.