(CANCERRESEARCH52, 6117-6120, November1, 19921 Advances in Brief Nonlinkage of 16q Markers to Familial Predisposition to Wilms' Tumor' Vicki Huff,2 Anthony E. Reeve, Mark Leppert, Louise C. Strong, Edwin C. Douglass, Clementina F. Geiser, Frederick P. Li, Anna Meadows, David F. Callen, Gilbert Lenoir, and Grady F. Saunders Departments ofBiochemist,y and Molecular Biology, Box 117 (V. H., G. F. S.] and Experimental Pediatrics, Box 209 fL C. £1, University ofTexas M. D. Anderson Cancer Center, Houston, Texas 77030; Molecular Carcinogenesis Laboratory, Department of Biochemistry, University of Otago, Dunedin, New Zealand (A. E. Rj; Howard Hughes Medical Institute, University of Utah Medical Center, Salt Lake City, Utah 84132 [M. Li; Department of Hemotology/Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105 (E. C. D.J; Department of Pediatrics, Division of Hematology/Oncology, University of Texas Health Science Center, San Antonio, Texas 78284 (C. F. G.J; Dana Farber Cancer Institute and Harvard School ofPublic Health, Boston, Massachusetts 02115 (F. P. U; Division ofOncology, Children's Hospital ofPhiladelphia, Philadelphia, Pennsylvania 19104 [A. M.J; Department ofCytogenetics and Molecular Genetics, Adelaide Children's Hospital, North Adelaide, 5.4. 5006, Australia ID. F. C.J; and International Agencyfor Research on Cancer, 69372 Lyon Cedex 08, France (G. L.] mutation with incomplete penetrance (13, 14). Five WT families were studied (pedigrees shown in Fig. 1) and include 24 affected individuals and 17 unaffected obligate carriers of the predisposition gene. Both male and female unaffected carriers were observed in the families, in dicating no salient effect ofparental imprinting on the penetrance of the segregating mutation. The ages of diagnosis ranged from 4 months (individual 000 in pedigree WTX524) to 9.5 years (individual 123 in pedigree WTX5O2),and both unilateral and bilateral tumors were ob served.Nokaryotypicabnormalitieshavebeenobserved.Twoofthese families (WTX5O2 and WTX524) were those in which 1lpl3 and 11p15 nonlinkage was originally reported (10, 11). In accordance with institutional guidelines, blood was obtained from the 84 individ uals whose identification numbers are underlined in the pedigrees shown in Fig. 1. They included 15 affected individuals and 16 obligate carriers. Restriction Fragment Length Polymorphism Typing. DNA was iso lated from peripheral blood lymphocytes and/or cultured lymphoblas toid cells. DNA samples were digested with the appropriate restriction endonucleases, electrophoresed on agarose gels, and transferred to ny lon membranes as previously described (15). The typed polymorphic loci spanned the l6q region (CETP to HP) at which tumor-specific LOH was observed (12) and encompassed an estimated 28 cM (l6).@ We used eight polymorphisms at five 16q loci for the multipoint anal yses (Fig. 2) (17). Linkage Analyses. Restriction fragment length polymorphism data were initially analyzed by two-point analysis using LIPED (data not shown). Subsequently, multipoint analyses were performed with the LINKAGE algorithm (version 4.8) of Lathrop et aL (18) using fixed genetic distances between markers (Fig. 2). All linkage results are re ported as lod scores in logarithm base 10. WT predisposition was modeled as an autosomal dominant trait with incomplete penetrance as noted above. Based on previous estimates, penetrance values of 0.4 and 0.6 and allele frequencies for the WT familial predisposition gene of 0.001 and 0.0001 were considered (13, 14). As presented below, the conclusions of these analyses were consistent using both sets of values. Published allele frequencies for the 16q polymorphic loci were used for the analyses (Fig. 2) (17). The sex-averaged genetic distances between the loci used are shown in Fig. 2 (l6).@ Results and Discussion Lod scores obtained by multipoint analyses were consistently less than —2.0 for the 16q markers (Table 1; Fig. 3), which provides sufficient evidence to exclude linkage of familial WT predisposition to the 16q region at which LOH was observed in approximately 20% of Wilms' tumors (12, 19). Analyses of the 16q marker data were performed using three sets of parameters (Table 1). Due to the variable estimates for the penetrance of the familial WT gene, penetrance values of 0.4 and 0.6 (Fig. 3; Table 1) were considered. When a value of0.4 was used, 4 D. F. Callen and H. M. Kozman, personal communication. AbstraCt Wilms' tumor (WT), a childhood cancer of the kidney, occurs in both familial and sporadic forms. Chromosome 11 genes have been impli cated in the etiology of WT, and mutations In a gene at chromosomal band 11p13, WTJ, have been identified In a few WT cases. However, 11p13 has been excluded as the site of the predisposition mutation segregating in several large WT families, which Implies the existence of a non-lip familial predisposition gene. Recently, loss of heterozygosity for 16q markers located between chromosomal bands 16q13 and 16q22 has been reported in approximately 20% ofsporadlc Wilms' tumors. To determine if this region of 16q harbors the non-lip familial WT gene, a genetic linkage study of five WT families was undertaken. Using multipoint analyses, we ruled out genetic linkage of familial WT pre disposition to i6q. Introduction WT3 is a childhood cancer of the kidney known to have a strong genetic component in its etiology. A gene, J-VJ'l, located at chromosomal band 11p13, has been isolated (1, 2), and mu tations at this locus have been identified in some WT patients (3—7). However, other genes are also thought to be important for tumorigenesis. Demonstration of tumor-specific LOH at 11p15 but not at 11p13 loci initially suggested that a gene located at 1ipi 5 is involved in tumorigenesis (8, 9). Further more, genetic linkage studies of several WT families have dem onstrated that WT predisposition in these families is not linked to either 1ipi 3 or 1ipi 5 loci, implying that yet another WT gene exists (10, 11). Recently, LOH at 16q loci has been re ported in approximately 20% of Wilms' tumors (12), which suggests that this genomic region harbors a gene important for WT development, possibly the gene responsible for WT predis position in the WT families in which 1ipi 3 and 1lplS have been excluded. To address this question we studied five WT families for genetic linkage to the 16q region (16q13—16q22) implicated in the chromosome 16q LOH study. Materials and Methods WT Families. Segregation analyses and epidemiological studies have suggested that familial WT is the result ofan autosomal dominant Received8/18/92;accepted9/16/92. The costs of publication of this article were defrayed in part by the payment of pagecharges. Thisarticle must thereforebe hereby marked advertisementin accord ance with 18 U.S.C. Section 1734 solely to indicate this fact. I Funded in part by a grant from the NIH and the University Cancer Fund. 2 To whom requests for reprints should be addressed, at Department of Bio chemistry and Molecular Biology, Box 117, University oflexas M. D. Anderson Cancer Center, 1515 HolcombeBoulevard,Houston, TX 77030. 3 The abbreviations used are: WT, Wilms' tumor, LOH, loss of heterozygosity, cM, centi Morgan; led, log ofthe odds ratio. 6117 Research. on October 8, 2021. © 1992 American Association for Cancer cancerres.aacrjournals.org Downloaded from