The hypodermis is the innermost and thickest layer of the skin. It invaginates into the dermis and is attached to the latter, immediately above it, by collagen and elastin fibres. It is essentially composed of a type of cells specialised in accumulating and storing fats, known as adipocytes.
Fatal familial insomnia Fatal familial insomnia (FFI) is a very rare, autosomal dominant inherited, disease of the brain. It is caused by a mutation in a protein called prion protein (PrP): asparagine-178 is replaced by aspartic acid.
The patient died at 58 (seven months after the onset of symptoms). An autopsy was completed post-mortem which revealed mild atrophy of the frontal cortex and moderate atrophy of the thalamus. The atrophy of the thalamus is one of the most common signs of fatal familial insomnia.