Prenatal testing and prenatal expectations Prenatal testing may be used to identify the existence of NF-1 in the fetus. For embryos produced via in vitro fertilisation, it is possible via preimplantation genetic diagnosis to screen for NF-1. Chorionic villus sampling or amniocentesis can be used to detect NF-1 in the fetus. While the presence of NF-1 can be identified through prenatal testing the severity with which the condition will be expressed is impossible to determine. People with NF-1 have a 50% percent chance of passing the disorder on to their kids, but people can have a child born with NF-1 when they themselves do not have it. This is caused in a spontaneous change in the genes during pregnancy. Post-natal testing The National Institutes of Health (NIH) has created specific criteria for the diagnosis of NF-1. Two of these seven "Cardinal Clinical Features" are required for positive diagnosis. There is practical flowchart to distinguish between<unk> , NF2 and schwannomatosis. * Six or more café-au-lait spots over 5 mm in greatest diameter in pre-pubertal individuals and over 15 mm in greatest diameter in post-pubertal individuals. Note that multiple café-au-lait spots alone are not a definitive diagnosis of NF-1 as these spots can be caused by a number of other conditions. * Two or more neurofibromas of any<unk>  or 1 plexiform neurofibroma * Freckling in the axillary (Crowe sign) or inguinal regions * Optic nerve glioma * Two or more Lisch nodules (pigmented iris hamartomas) * A distinctive osseous lesion such as sphenoid dysplasia, or thinning of the long bone cortex with or without pseudarthrosis. * A first degree relative (parent, sibling, or offspring) with NF-1 by the above criteria.
Neurofibromatosis type I
Legius syndrome
Neurofibromatosis type 4
Tuberous sclerosis
Von Hippel–Lindau disease
Fox–Fordyce disease
Progeria
Fabry disease