Mosaic Chromosome 6 Trisomy in an Epidermal Nevus

Abstract

We report a 2-year-old boy with a linear epidermal nevus. Mosaicism for chromosome 6 in skin fibroblasts of affected skin was discovered. Trisomy 6 has not been previously implicated as an isolated finding in epidermal nevi or cutaneous mosaicism.

Epidermodysplasia verruciformis–associated and genital-mucosal high-risk human papillomavirus DNA are prevalent in nevus sebaceus of Jadassohn

“…96 In human beings, abnormal karyotypes have been associated with HPV infection during pregnancy 81,91 implicating initiation of chromosomal instability. Mosaic chromosome 6 trisomy has been described in a case of EN 97 and deletions (loss of heterozygosity) of the PATCHED gene and other chromosomal losses have been detected in NS 13 incriminating chromosomal instability as one pathway to mosaicism and development of EN and NS. High-risk HPV viral integration and expression of oncoproteins E6 and E7 are established causes of genomic instability such as complex chromosomal abnormalities.…”

Chromosome 6 Abnormality with Associated Dysmorphological Features and Erythrokeratoderma

“…In Sobey et al (1) “Mosaic Chromosome 6 Trisomy in an Epidermal Nevus,” the authors document a case which showed skin biopsy findings of a mosaic trisomy 6 from a linear epidermal nevus. Previously, chromosome 6 mosaicism has only been reported in an infant, with multiple other genetic abnormalities.…”

First Case of Maffucci Syndrome Associated with Multiple Epidermal Nevi

“…Multiple hypothesis have been reported, including a mutation of the parathormone receptor 1 (PTHRP1) [8], chromosomal rearrangements affecting chromosomes 1 and/or 6 [9][10][11][12], dysembryoplasias affecting different territories [3]. According to Happle, sporadic syndromes with mosaic skin defects could be due to a gametic mutation or to an early somatic mutation [13].…”