Mutations in the fumarate hydratase gene cause hereditary leiomyomatosis and renal cell cancer in families in North America

Abstract

Hereditary leiomyomatosis and renal cell cancer (HLRCC) is an autosomal dominant disorder characterized by smooth-muscle tumors of the skin and uterus and/or renal cancer. Although the identification of germline mutations in the fumarate hydratase (FH) gene in European families supports it as the susceptibility gene for HLRCC, its role in families in North America has not been studied. We screened for germline mutations in FH in 35 families with cutaneous leiomyomas. Sequence analysis revealed mutations in FH in 31 families (89%). Twenty different mutations in FH were identified, of which 18 were novel. Of these 20 mutations, 2 were insertions, 5 were small deletions that caused frameshifts leading to premature truncation of the protein, and 13 were missense mutations. Eleven unrelated families shared a common mutation: R190H. Eighty-one individuals (47 women and 34 men) had cutaneous leiomyomas. Ninety-eight percent (46/47) of women with cutaneous leiomyomas also had uterine leiomyomas. Eighty-nine percent (41/46) of women with cutaneous and uterine leiomyomas had a total hysterectomy, 44% at age < or =30 years. We identified 13 individuals in 5 families with unilateral and solitary renal tumors. Seven individuals from four families had papillary type II renal cell carcinoma, and another individual from one of these families had collecting duct carcinoma of the kidney. The present study shows that mutations in FH are associated with HLRCC in North America. HLRCC is associated with clinically significant uterine fibroids and aggressive renal tumors. The present study also expands the histologic spectrum of renal tumors and FH mutations associated with HLRCC.

Figure  1

Clinical, histologic, and radiologic manifestations of HLRCC. A, Segmental distribution of leiomyomas in a 32-year-old man. Clinically, cutaneous leiomyomas presented as firm skin-colored to light-brown-colored papules and nodules. B, Histology of cutaneous leiomyoma. Leiomyomas were a proliferation of interlacing bundles of smooth-muscle fibers with a centrally located long blunt-edged nucleus in the dermis. C, Abdominal CT scan, showing the location of a renal tumor in the 32-year-old man shown in panel A. The resected neoplasm was a papillary type II renal cell carcinoma, as shown in panel D. D, Histologic findings of papillary type II renal cell carcinoma. There is a distinct papillary architecture. Cells had an abundant amphophilic cytoplasm and large nuclei with large inclusion-like eosinophilic nucleoli. Magnification × 200.

Figure  2

Age distribution at diagnosis of uterine fibroids (red) and reported age distribution at onset of cutaneous leiomyomas (blue)

Figure  3

Physical map of the FH critical region on 1q42.3 A, Ideogram of human chromosome 1q long arm with some markers at 1q42.3-43, with integrated genetic map (above) and physical map (below), showing locations of selected polymorphic markers. Cent. = centromere; Tel. = telomere. B, Expanded physical map. The BAC tiling path is shown by blue horizontal lines and GenBank clone ID numbers. BAC overlaps were confirmed in silico. A sequence gap is present in the 2.6-Mb region. C, Locations of known genes, shown within the 2.6-Mb region of FH. Seven known genes were identified and confirmed by searching public and private databases. D, FH exon-intron structure and mutations identified in the exonic sequence.

Figure  4

FH mutations in patients with HLRCC. Sequencing chromatograms of genomic DNA from control subjects and patients are shown at left (arrows indicate the position of the identified nucleotide changes), and pedigrees are shown at right (asterisks indicate history of renal cancer). The delA at nucleotide 1162 (A), a delG at nucleotide 1339 (D), a delGC at nucleotides 780 and 781 (E), and an 8-bp duplication at nucleotides 1300–1307 (F) cause shifts in the reading frame that lead to a stop codon downstream and truncate the corresponding protein; a missense mutation, G569A (B), changes an arginine to a histidine at codon 190, and another missense mutation, C823T (C), changes a histidine to a tyrosine at codon 275. Sequences containing insertions and deletions are derived from subcloned alleles from affected patients.

Figure  4

FH mutations in patients with HLRCC. Sequencing chromatograms of genomic DNA from control subjects and patients are shown at left (arrows indicate the position of the identified nucleotide changes), and pedigrees are shown at right (asterisks indicate history of renal cancer). The delA at nucleotide 1162 (A), a delG at nucleotide 1339 (D), a delGC at nucleotides 780 and 781 (E), and an 8-bp duplication at nucleotides 1300–1307 (F) cause shifts in the reading frame that lead to a stop codon downstream and truncate the corresponding protein; a missense mutation, G569A (B), changes an arginine to a histidine at codon 190, and another missense mutation, C823T (C), changes a histidine to a tyrosine at codon 275. Sequences containing insertions and deletions are derived from subcloned alleles from affected patients.