Perinatal. Referring to the period of time surrounding an infant's birth, from the last two months of pregnancy to the first 28 days of life. The TORCH panel tests for perinatal infections.
1 CMT1 is commonly caused by a duplication of a gene on chromosome 17. This gene controls the production of your nervesâ protective myelin sheath. CMT1 is also caused by other gene defects.  CMT2 results from a defect in your peripheral nerve cellsâ axon. This is caused by a defect in your mitofusin 2 gene.
Cri-du-chat (cat's cry) syndrome is caused by a deletion of the end of the short (p) arm of chromosome 5. This chromosomal change is written as 5p- (5p minus). The signs and symptoms of cri-du-chat syndrome are probably related to the loss of multiple genes in this region.wo copies of chromosome 5, one copy inherited from each parent, form one of the pairs. Chromosome 5 spans about 181 million DNA building blocks (base pairs) and represents almost 6 percent of the total DNA in cells.