The Journal of Clinical Endocrinology & Metabolism Vol. 82, No. 9 3025-3028
Copyright © 1997 by The Endocrine Society
Mutation Analysis of Glial Cell Line-Derived Neurotrophic Factor, a Ligand for an RET/Coreceptor Complex, in Multiple Endocrine Neoplasia Type 2 and Sporadic Neuroendocrine Tumors
Debbie J. Marsh,
Zimu Zheng,
Andrew Arnold1,
Scott D. Andrew,
Diana Learoyd,
Andrea Frilling,
Paul Komminoth,
Hartmut P.H. Neumann,
Bruce A.J. Ponder2,
Barrett J. Rollins,
Geoffrey I. Shapiro,
Bruce G. Robinson,
Lois M. Mulligan and
Charis Eng3
Department of Adult Oncology (D.J.M., Z.Z., B.J.R., G.I.S., C.E.)
and Human Cancer Genetics Unit (D.J.M., Z.Z., C.E.), Dana-Farber Cancer
Institute, Department of Medicine (D.J.M., Z.Z., A.A., B.J.R., G.I.S.,
C.E.), Harvard Medical School, Boston, MA; Laboratory of Endocrine
Oncology (A.A.), Massachusetts General Hospital, Boston, MA; Molecular
Genetics Laboratory, Kolling Institute for Medical Research (S.D.A.,
D.L., B.G.R.), Royal North Shore Hospital, University of Sydney, St.
Leonards, New South Wales, Australia; Department of Surgery (A.F.),
Eppendorf University of Hamburg, Hamburg, Germany; Department of
Pathology (P.K.), University of Zurich, Zurich, Switzerland; Division
of Nephrology (H.P.H.N.), Department of Internal Medicine IV,
Albert-Ludwigs University of Freiburg, Freiburg, Germany; CRC Human
Cancer Genetics Research Group (B.A.J.P.), University of Cambridge,
Cambridge, UK; and Departments of Pathology and Paediatrics (L.M.M.),
Queens University, Kingston, Ontario, Canada
Address all correspondence and requests for reprints to: Charis Eng, Dana-Farber Cancer Institute, 44 Binney Street, Boston, Massachusetts 02115-6084.
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Abstract
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Causative germline missense mutations in the RET
proto-oncogene have been associated with over 92% of families with the
inherited cancer syndrome multiple endocrine neoplasia type 2 (MEN 2).
MEN 2A is characterized primarily by medullary thyroid carcinoma (MTC)
and pheochromocytoma, both tumors of neural crest origin. Parathyroid
hyperplasia or adenoma is also seen in MEN 2A, but rarely in MEN 2B,
which has additional stigmata, including a marfanoid habitus, mucosal
neuromas, and ganglioneuromatosis of the gastrointestinal tract. In
familial MTC, MTC is the only lesion present. Somatic
RET mutations have also been identified in a subset of
sporadic MTCs, pheochromocytomas, and rarely, small cell lung cancer,
but not in sporadic parathyroid hyperplasias/adenomas or other
neuroendocrine tumors. Glial cell line-derived neurotrophic factor
(GDNF) and its receptor molecule GDNFR-
, have recently been
identified as members of the RET ligand binding complex. Therefore, the
genes encoding both GDNF and GDNFR-
are excellent candidates for a role in the pathogenesis of those MEN 2
families and sporadic neuroendocrine tumors without RET
mutations. No mutations were found in the coding region of
GDNF in DNA samples from 9 RET mutation
negative MEN 2 individuals (comprising 6 distinct families), 12
sporadic MTCs, 17 sporadic cases of parathyroid adenoma, and 10 small
cell lung cancer cell lines. Therefore, we find no evidence that
mutation within the coding regions of GDNF plays a role
in the genesis of MEN 2 and sporadic neuroendocrine tumors.
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Introduction
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GERMLINE MISSENSE mutations in the
RET proto-oncogene, which encodes a tyrosine kinase
receptor, have been identified in over 92% of families who have the
familial cancer syndrome multiple endocrine neoplasia type 2 (MEN 2)
(1). MEN 2 is characterized by tumors of neuroendocrine origin,
specifically medullary thyroid carcinoma (MTC) and pheochromocytoma
[reviewed by Eng (2)]. In familial MTC (FMTC), MTC is the only tumor
present. In classic MEN 2A, MTC occurs in combination with
pheochromocytoma and parathyroid hyperplasia or adenoma. MEN 2B
patients develop identical lesions to those found in MEN 2A,
with the exception of parathyroid hyperplasia or adenoma, while also
manifesting characteristic abnormalities, including a marfanoid
habitus, mucosal neuromas, and ganglioneuromatosis of the
gastrointestinal tract (3).
Although clearly being components of MEN 2, MTC, pheochromocytoma, and
parathyroid hyperplasia or adenoma occur as sporadic tumors in the
majority of cases (4, 5, 6). Somatic RET mutations have been
identified in sporadic MTCs at frequencies varying between 2386%
depending on the sample size and population studied (7, 8, 9, 10, 11, 12, 13, 14). In
sporadic pheochromocytoma, somatic RET mutations, and
mutations in the gene for von Hippel-Lindau disease (VHL),
have been identified in approximately 10% and 1.5% of tumors,
respectively (6, 7, 15, 16, 17, 18, 19). Although RET is expressed in
the developing parathyroid glands and parathyroid tumors, sequence
analysis of the gene has yet to reveal a somatic mutation (20, 21, 22, 23, 24). A
similar situation pertains in many other sporadic neuroendocrine tumors
such as pituitary tumors and melanoma (23). However, 2 of 60 small cell
lung carcinoma (SCLC) cell lines have been shown to have a non-MEN
2-type RET exon 11 mutation (25, 26). Clearly, other
etiologies need to be sought.
Recently, glial cell line-derived neurotrophic factor (GDNF),
mapping to chromosome 5p13.1-p13.3 (27, 28), and its receptor molecule
GDNFR-
have been shown to participate in RET activation (29, 30, 31).
GDNF belongs to the transforming growth factor-ß superfamily and is
known to enhance the survival of midbrain dopaminergic neurons (32).
Currently, it is believed that GDNF binds GDNFR-
, which in turn
binds RET to form a heterohexameric complex. Because GDNF and GDNFR-
appear to be involved in the RET signaling pathway, their genes
represent excellent candidates for roles in the genesis of sporadic
neuroendocrine tumors and RET-negative MEN 2 families.
In this study, we examined RET mutation negative MEN 2
patients, sporadic MTCs, parathyroid adenomas, and SCLC lines to
determine whether mutations in the exons of GDNF are
involved in their pathogenesis.
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Subjects and Methods
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Patients and tumor specimens
The diagnosis of MEN 2 was made according to the classical
criteria and those of the International RET Mutation
Consortium (1, 33). Constitutive DNA from affected individuals from 6
unrelated MEN 2 families without RET mutation, 2 MEN 2A, 2
MEN 2B and 2 FMTC, was analyzed for mutations in GDNF.
Patients with sporadic tumors were those without other family members
with neuroendocrine tumors and without known histories of MEN 1, MEN 2,
or VHL as outlined previously (6). A total of 39 sporadic
neuroendocrine tumors, 12 MTC, 17 parathyroid adenoma, and 10 SCLC
lines without RET mutation were analyzed. Sporadic
pheochromocytomas have been analyzed for GDNF mutations and
reported elsewhere (34, 35). The following SCLC lines, shown previously
to lack wild-type RB1, and retain a normal
p16Ink4A gene (36, 37, 38), were obtained
from American Type Culture Collection (Rockville, MD) and maintained in
RPMI 1640 supplemented with 10% FCS, penicillin, and streptomycin:
NCI-H82 (HTB-175), NCI-H69 (HTB-119), NCI-H128 (HTB-120), NCI-H446
(HTB-171), NCI-H146 (HTB-173), NCI-H187 (CRL-5804), NCI-H378
(CRL-5808), NCI-N417 (CRL-5809), NCI-H526 (CRL-5811) and NCI-H889
(CRL5817).
All work with human samples has been approved by the IRB under
Dana-Farber Cancer Institute Protocol 94138.
DNA extraction and PCR amplification of GDNF
Constitutional DNA was obtained by extraction from the
patients peripheral blood leukocytes using standard procedures (39).
High molecular weight DNA was obtained from tumor tissue by
phenol-chloroform extraction and ethanol precipitation (39).
All PCR products were generated using a Touchdown Thermal Cycler
(Hybaid Ltd., Middlesex, UK). A 186-nucleotide PCR product
corresponding to the first exon of GDNF was PCR amplified
using the oligonucleotide primers GDNF-X1FL
(5'-TGTAAAACGACGGCCA-GTTGAAGTTATGGGATGTCGTGGCTGTCT-3') and
GDNF-X1R(5'C-AGGAAACAGCTATGACCAGTCACTGCTCAGCGCGAAGG-3') and the
following protocol: 95 C x 5 min followed by 35 cycles of 95 C x 1
min, 61 C x 1 min, 72 C x 1 min, and a final extension at 72 C
for 10 min. The final concentration of PCR reagents were as follows:
0.8 µM of each primer; 0.2 mM of each
deoxynucleotide triphosphate, 1x PCR buffer containing 1.5
mM MgCl2 (Perkin-Elmer Corp., Norwalk, CT) and
2 U Taq polymerase (Perkin-Elmer Corp.) in combination with
TaqStart Antibody used as recommended by the manufacturer (Clontech
Laboratories, Palo Alto, CA). Exon 2 of GDNF was PCR
amplified using the primers GDNF-X2F
(5'-TGTAAAACGACGGCCAGTTCCTAGAAGAGAGCGGAATCG-3') or GDNF-2F
(5'-TGTAAAACGACGGCCAGTAAATATGCCAGAGGATTATCCTGA-3') and GDNF-3R
(5'-CAGGAAACAGCTATGACCCAGATACATCCACACCTTTTAGCG-3') to generate a PCR
product of 454 or 485 nucleotides, respectively. The PCR conditions
used were similar to those for exon 1 except for annealing at 60 C for
30 sec and a final concentration of 0.4 µM of each
primer. All forward primers contained -21 m13F and reverse primers
-21 m13R sequences attached to the 5' ends. All PCRs were performed in
a final reaction volume of 50 µl.
GDNF sequencing
Cycle sequencing was performed using the ABI Prism Dye Primer
Cycle Sequencing Ready Reaction Kit (Perkin-Elmer Corp.) and the
GeneAmp PCR System 9600 (Perkin-Elmer Corp.). The products of cycle
sequencing were electrophoresed on a 6% Long Ranger gel (FMC
Bioproducts, Rockland, ME) and analyzed on an Applied Biosystems
automated DNA sequencer (Perkin-Elmer Corp.).
 |
Results
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Sequence analysis of both exons of GDNF in genomic DNA
from 6 unrelated RET mutation-negative MEN 2 individuals did
not identify any sequence variants (Table 1
). Similarly, no GDNF
mutations were detected in 12 sporadic MTCs, 17 sporadic parathyroid
adenomas, and 10 SCLC cell lines.
 |
Discussion
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No GDNF mutations were detected in 6 unrelated MEN 2
families and 39 sporadic MEN 2-related and other neuroendocrine tumors.
In addition, because PCR product sizes were those expected, it is
unlikely that gross rearrangements occurred. However, mutations in the
promoter region, which is not well characterized, or deep within the
intron, would not have been detected in this study.
With recent data demonstrating that GDNF acts as a natural ligand for
RET (30, 31, 40), and that the GDNF knockout mouse has a
similar phenotype to that for ret, GDNF became an
obvious candidate to play a major role in both Hirsch-sprung
disease (HSCR) and those MEN 2 families and sporadic related tumors
without RET mutations. The major susceptibility gene for
HSCR, a disease caused by the congenital absence of enteric neurons
(41), is RET (42, 43, 44, 45). True to predictions, the phenotype of
the murine knockout model for GDNF is absence of enteric
ganglia and renal agenesis (46, 47, 48). Yet, contrary to these data, only
6 of 315 HSCR cases (<2%) had germline GDNF mutations
(49, 50, 51).
Mutations of GDNF that cause either gain or loss of function
could lead to neoplasia, specifically, MEN 2, or sporadic
neuroendocrine tumor. Gain of function mutations could be involved in
at least three situations: 1) increased expression, which has been
excluded in sporadic pheochromocytomas (34); 2) gene amplification,
which, again has been excluded in sporadic pheochromocytomas (34); and
3) missense mutations, which lead to possible better fit of ligand to
its receptor and coreceptor. Loss of function mutations might be
plausible if we postulate that more than one ligand exists for RET;
differential use of competing ligands could lead to a pathological
response and hence, neoplasia. A GDNF-like molecule has been shown to
exist (52). Interestingly, of 45 sporadic pheochromocytomas without
somatic or germline RET or VHL mutations in two
series, one was found to have a GDNF R93W mutation that
turned out to be germline in origin (34, 35). This is the identical
mutation found in two HSCR cases (49, 50). Although somewhat puzzling
given the current state of knowledge, this observation could lend some
credence to the tissue-specific, differential ligand usage theory.
The current study suggests that if mutation of GDNF were to
play a role in the development of MEN 2, its component sporadic tumors,
and other endocrine tumors originating from the neural crest, as seems
to be the case in HSCR, its role is indeed a subtle one. The very small
number of polymorphisms, recognized as conservative amino acid
substitutions, provide evidence that sequence alterations in this gene
are very infrequent (34, 49, 50). It is perhaps not surprising because
of the size of the coding region. Another possibility is that
heterozygous activating mutations in GDNF may be highly
deleterious to the developing human embryo, resulting in embryonic
lethals. This is plausible in view of the widespread expression of
GDNF. Whether GDNFR-
, the third known component of the
RET/coreceptor/ligand complex, will harbor mutations resulting in the
activation of RET is currently being explored.
 |
Acknowledgments
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We gratefully acknowledge Anastasia Satterfield and Anne-Louise
Richardson for assistance and Sharice Abdillahi for administrative
support.
 |
Footnotes
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1 Recipient of an American Cancer Society Faculty Research Award. 
2 A Gibb Fellow of the Cancer Research Campaign. 
3 Lawrence and Susan Marx Investigator in Human Cancer Genetics and
a Patterson Fellow and is also supported by the Markey Charitable
Trust, the Charles A. Dana Foundation, the American Cancer Society
(RPG-97064-01 VM), and the Harvard Nathan Shock Center of Excellence
Award in the Basic Biology of Aging (1P30AG1331401). 
Received February 24, 1997.
Accepted May 30, 1997.
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References
|
|---|
-
Eng C, Clayton D, Schuffenecker I, et al. 1996 The relationship between specific RET proto-oncogene
mutations and disease phenotype in multiple endocrine neoplasia type 2:
International RET Mutation Consortium Analysis. JAMA. 276:15751579.[Abstract/Free Full Text]
-
Eng C. 1996 The RET proto-oncogene in
multiple endocrine neoplasia type 2 and Hirschsprung disease. N
Engl J Med. 335:943951.[Free Full Text]
-
Schimke RN, Hartmann WH, Prout TW, Rimoin DL. 1968 Syndrome of bilateral pheochromoctyoma, medullary thyroid carcinoma and
multiple neuromas. N Engl J Med. 279:17.
-
Eng C, Ponder BAJ. 1993 The role of gene mutations
in the genesis of familial cancers. FASEB J. 7:910919.[Abstract]
-
Eng C, Mulligan LM, Smith DP, et al. 1995 Low
frequency of germline mutations in the RET proto-oncogene in
patients with apparently sporadic medullary thyroid carcinoma. Clin
Endocrinol (Oxf). 43:123127.[Medline]
-
Eng C, Crossey PA, Mulligan LM, et al. 1995 Mutations of the RET proto-oncogene and the von
Hippel-Lindau disease tumour suppressor gene in sporadic and syndromic
phaeochromocytoma. J Med Genet. 32:934937.[Abstract/Free Full Text]
-
Eng C, Smith DP, Mulligan LM, et al. 1994 Point
mutation within the tyrosine kinase domain of the RET
proto-oncogene in multiple endocrine neoplasia type 2B and related
sporadic tumours. Hum Mol Genet. 3:237241.[Abstract/Free Full Text]
-
Eng C, Mulligan LM, Smith DP, et al. 1995 Mutation
in the RET proto-oncogene in sporadic medullary thyroid
carcinoma. Genes Chromosomes Cancer. 12:209212.[Medline]
-
Hofstra RMW, Landsvater RM, Ceccherini I, et al. 1994 A mutation in the RET proto-oncogene associated with
multiple endocrine neoplasia type 2B and sporadic medullary thyroid
carcinoma. Nature. 367:375376.[CrossRef][Medline]
-
Blaugrund JE, Johns MM, Eby YJ, et al. 1994 RET proto-oncogene mutations in inherited and sporadic
medullary thyroid cancer. Hum Mol Genet. 3:18951897.[Free Full Text]
-
Zedenius J, Wallin G, Hamberger B, Nordenskjöld M,
Weber G, Larsson C. 1994 Somatic and MEN 2A de novo
mutations identified in the RET proto-oncogene by screening of sporadic
MTCs. Hum Mol Genet. 3:12591262.[Abstract/Free Full Text]
-
Zedenius J, Larsson C, Bergholm U, et al. 1995 Mutations of codon 918 in the RET proto-oncogene correlate
to poor prognosis in sporadic medullary thyroid carcinoma. J Clin
Endocrinol Metab. 80:30883090.[Abstract/Free Full Text]
-
Komminoth P, Kunz EK, Matias-Guiu X, et al. 1995 Analysis of RET proto-oncogene point mutations distinguishes
heritable from nonheritable medullary thyroid carcinomas. Cancer. 76:479489.[CrossRef][Medline]
-
Marsh DJ, Learoyd DL, Andrew SD, et al. 1996 Somatic mutations in the RET proto-oncogene in sporadic
medullary thyroid carcinoma. Clin Endocrinol (Oxf). 44:249257.[CrossRef][Medline]
-
Komminoth P, Kunz E, Hiort O, et al. 1994 Detection
of RET proto-oncogene point mutations in paraffin-embedded
pheochromocytoma specimens by nonradioactive single-strand conformation
polymorphism analysis and direct sequencing. Am J Pathol. 145:922929.[Abstract]
-
Chew SL, Lavender P, Jain A, et al. 1995 Absence of
mutations in the MEN2A region of the ret
proto-oncogene in non-MEN 2A phaeochromocytomas. Clin Endocrinol (Oxf). 42:1721.[Medline]
-
Beldjord B, Desclaux-Arramond F, Raffin-Sanson M, et
al. 1995 The RET proto-oncogene in sporadic
pheochromocytomas: frequent MEN 2-like mutations and new molecular
defects. J Clin Endocrinol Metab. 80:20632068.[Abstract]
-
Lindor NM, Honchel R, Khosla S, Thibodeau SN. 1995 Mutations in the RET protooncogene in sporadic
pheochromocytomas. J Clin Endocrinol Metab. 80:627629.[Abstract]
-
Hofstra RMW, Stelwagen T, Stulp RP, et al. 1996 Extensive mutation scanning of RET in sporadic medullary
thyroid carcinoma and of RET and VHL in sporadic
pheochromocytoma reveals involvement of these genes in only a minority
of cases. J Clin Endocrinol Metab. 81:28812884.[Abstract/Free Full Text]
-
Pachnis V, Mankoo B, Constantini F. 1993 Expression
of the c-ret proto-oncogene during mouse embryogenesis. Development. 119:10051017.[Abstract]
-
Pausova Z, Soliman E, Amizuka N, et al. 1996 Role
of the RET proto-oncogene in sporadic hyperparathyroidism
and in hyperparathyroidism of multiple endocrine neoplasia type 2. J Clin Endocrinol Metab. 81:27112718.[Abstract]
-
Padberg B-C, Schröder S, Jochum W, et al. 1995 Absence of RET proto-oncogene point mutations in
sporadic hyperplastic and neoplastic lesions of the parathyroid gland. Am J Pathol. 147:16001607.[Abstract]
-
Komminoth P, Roth J, Muletta-Feurer S, Saremaslani P,
Seelentag WKF, Heitz PU. 1996 RET proto-oncogene point
mutations in sporadic neuroendocrine tumors. J Clin Endocrinol
Metab. 81:20412046.[Abstract]
-
Williams GH, Carss RA, Cummins G, Thomas GA, Williams
ED. 1996 Analysis of the RET proto-oncogene in sporadic
parathyroid adenomas. J Pathol. 180:138141.[CrossRef][Medline]
-
Futami H, Egawa S-i, Yamaguchi K. 1994 A novel
point mutation of the RET proto-oncogene in small cell lung
carcinoma cell lines. Proc Jpn Acad. 70B:210214.
-
Mulligan LM, Ivanchuk SM, Campling BG, Sundaresan V,
Rabbits PH, Eng C. 1996 Analysis of RET and the RET
ligand (GDNF) in small cell lung carcinoma. Am J Hum
Genet. 59S:A345 (2010).
-
Schindelhauer D, Schuffenhauer S, Glasser T,
Steinkasserer A, Meitinger T. 1995 The gene coding for glial cell
line derived neurotrophic factor (GDNF) maps to chromosome 5p12p13.1. Genomics. 28:605607.[CrossRef][Medline]
-
Bermingham N, Hillermann R, Gilmour F, Martin JE, Fisher
EMC. 1995 Human glial cell line-derived neurotrophic factor (GDNF)
maps to chromosome 5. Hum Genet. 96:671673.[CrossRef][Medline]
-
Durbec P, Marcos-Gutierrez CV, Kilkenny C, et al. 1996 Glial cell line-derived neurotrophic factor signalling through the
Ret receptor tyrosine kinase. Nature. 381:789793.[CrossRef][Medline]
-
Jing S, Wen D, Yu Y, et al. 1996 GDNF-induced
activation of the Ret protein tyrosine kinase is mediated by GDNFR-a, a
novel receptor for GDNF. Cell. 85:11131124.[CrossRef][Medline]
-
Treanor JJS, Goodman L, de Sauvage F, et al. 1996 Characterization of a multicomponent receptor for GDNF. Nature. 382:8083.[CrossRef][Medline]
-
Lin L-FH, Doherty DH, Lile JD, et al. 1993 GDNF: a
glial cell line-derived neurotrophic factor for midbrain dopamingergic
neurons. Science. 260:11301132.[Abstract/Free Full Text]
-
Mulligan LM, Marsh DJ, Robinson BG, et al. 1995 Genotype-phenotype correlation in MEN 2: report of the International
RET Mutation Consortium. J Intern Med. 238:343346.[Medline]
-
Dahia PLM, Toledo SPA, Mulligan LM, Maher ER, Grossman
AB, Eng C. 1997 Mutation analysis of glial cell line-derived
neurotrophic factor, GDNF, a ligand for the RET/GDNF receptor a
complex, in sporadic phaeochromocytomas. Cancer Res. 57:310313.[Abstract/Free Full Text]
-
Woodward ER, Eng C, McMahon R, Affara NA, Ponder BAJ,
Maher ER. 1997 Genetic predisposition to phaeochromocytoma:
analysis of candidate genes GDNF, RET and
VHL. Hum Mol Genet. In press.
-
Shapiro GI, Edwards CD, Kobzik L, et al. 1995 Reciprocal RB inactivation and P16(Ink4) expression in primary lung
cancers and cell lines. Cancer Res. 55:505509.[Abstract/Free Full Text]
-
Otterson GA, Kratzke RA, Coxon A, Kim YW, Kaye FJ. 1994 Absence of p16INK4 protein is restricted to the subset of lung
cancer cell lines that retains wildtype RB. Oncogene. 9:33753378.[Medline]
-
Harbour JW, Lai SL, Whang-Peng J, Gazdar AF, Minna
JD. 1988 Abnormalities in structure and expression of the human
retinoblastoma gene in SCLC. Science. 241:353357.[Abstract/Free Full Text]
-
Mathew CGP, Smith BA, Thorp K, et al. 1987 Deletion
of genes on chromosome 1 in endocrine neoplasia. Nature. 328:524526.[CrossRef][Medline]
-
Trupp M, Arenas E, Fainzilber M, et al. 1996 Functional receptor for GDNF encoded by the c-ret
proto-oncogene. Nature. 381:785789.[CrossRef][Medline]
-
Okamoto E, Ueda T. 1967 Embryogenesis of intramural
ganglia of the gut and its relation to Hirschsprung disease. J
Pediatr Surg. 10:437443.[CrossRef]
-
Edery P, Lyonnet S, Mulligan LM, et al. 1994 Mutations of the RET proto-oncogene in Hirschsprungs
disease. Nature. 367:378380.[CrossRef][Medline]
-
Romeo G, Ronchetto P, Luo Y, et al. 1994 Point
mutations affecting the tyrosine kinase domain of the RET
proto-oncogene in Hirschsprungs disease. Nature. 367:377378.[CrossRef][Medline]
-
Angrist M, Bolk S, Thiel B, et al. 1995 Mutation
analysis of the RET receptor tyrosine kinase in Hirschsprung disease. Hum Mol Genet. 4:821830.[Abstract/Free Full Text]
-
Attié T, Pelet A, Edery P, et al. 1995 Diversity of RET proto-oncogene mutations in familial and
sporadic Hirschsprung disease. Hum Mol Genet. 4:13811386.[Abstract/Free Full Text]
-
Sánchez MP, Silos-Santiago I, Frisén J, He
B, Lira SA, Barbacid M. 1996 Renal agenesis and the absence of
enteric neurons in mice lacking GDNF. Nature. 382:7073.[CrossRef][Medline]
-
Pichel JG, Shen L, Sheng HZ, et al. 1996 Defects in
enteric innervation and kidney development in mice lacking GDNF. Nature. 382:7376.[CrossRef][Medline]
-
Moore MW, Klein RD, Farinas I, et al. 1996 Renal
and neuronal abnormalities in mice lacking GDNF. Nature. 382:7679.[CrossRef][Medline]
-
Angrist M, Bolk S, Halushka M, Lapchak PA, Chakravarti
A. 1996 Germline mutations in glial cell line-derived neurotrophic
factor (GDNF) and RET in a Hirschsprung disease
patient. Nature Genet. 14:341344.[CrossRef][Medline]
-
Salomon R, Attié T, Pelet A, et al. 1996 Germline mutations of the RET ligand, GDNF, are not sufficient to cause
Hirschsprung disease. Nature Genet. 14:345347.[CrossRef][Medline]
-
Ivanchuk SM, Myers SM, Eng C, Mulligan LM. 1996 De novo mutation of GDNF, ligand for RET/GDNFR-a receptor
complex in Hirschsprung disease. Hum Mol Genet. 5:20232026.[Abstract/Free Full Text]
-
Kotzbauer PT, Lampe PA, Heuckeroth RO, et al. 1996 Neurturin, a relative of glial-cell-line-derived neurotrophic factor. Nature. 384:467470.[CrossRef][Medline]
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