Familial Segmental Neurofibromatosis

Abstract

Segmental neurofibromatosis is considered to be the result of postzygotic NF1 gene mutations. We present a family in which the proband has generalized neurofibromatosis 1, whereas members of previous generations manifest segmental skin lesions. All, including the clinically asymptomatic grandmother, carry the same haplotype. This is the only case in the literature in which a parent with segmental skin findings has a child with full-blown neurofibromatosis 1 disease. The genetic mechanisms underlying this association are discussed. This family can be further investigated by examination of tissue samples from affected and unaffected sites for mutations.

A unique case of hereditary bilateral segmental neurofibromatosis on the face

“…Generally, there is no family history of similar disorder in patients with SN and it has been reported in only eight cases. 2 This is probably the fifth reported case of SN affecting the face and ninth reported case of familial occurrence, as well as the first report in which an individual is affected with hereditary segmental and bilateral neurofibromatosis. To conclude, this case of SN is reported for its rarity and atypical occurrence.…”

Giant café-au-lait macule in neurofibromatosis 1: A type 2 segmental manifestation of neurofibromatosis 1?

“…Most patients with segmental NF1 do not have a family history of neurofibromatosis, although they are at a moderately increased risk to transmit the trait to their children in the form of nonmosaic NF1. [18][19][20] Among 185 segmental NF1 cases collected by Huson and Ruggieri, 21 there were 10 cases having offspring with classical nonsegmental disease. The concept of a postzygotic mutation giving rise to type 1 segmental NF1 has recently been proven at the molecular level.…”

“…Most of such reports can today plainly be explained by the occurrence of type 2 segmental NF1 either in the parent or in the offspring, 24,25 whereas other cases are not well documented and thus doubtful. 19 Several autosomal dominant skin diseases exemplify the concept of type 2 segmental manifestation (Table I). 26,27 Among them, a strikingly high frequency of this form of mosaicism has been documented in cutaneous leiomyomatosis, glomangiomatosis, and disseminated superficial actinic porokeratosis.…”

Segmental neurofibromatosis: A report of 3 cases

“…Gonadal mosaicism is thought to be responsible for reports of patients with localized disease having children with generalized NF1. [78]…”