Novel germline mutations of the MEN1 gene in Greek families with multiple endocrine neoplasia type 1.
BACKGROUND
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant hereditary disorder associated with mutations of the MEN1 gene and characterized by the combined occurrence of tumours of the parathyroid glands, the pancreatic islet cells and the anterior pituitary.


OBJECTIVE
To identify MEN1 gene mutations and characterize clinical manifestations in Greek patients with MEN1.


METHODS
We studied four unrelated index patients with MEN1, 17 relatives and 100 control subjects. Among the relatives, seven were clinically and/or biochemically affected, while 10 were unaffected. DNA extraction, polymerase chain reaction (PCR) and direct sequencing of the MEN1 exons 2-10 and exon/intron boundaries were performed according to standard procedures.


RESULTS
We identified novel MEN1 gene mutations in three out of four index patients (75%) and in all affected (100%) relatives. Novel mutations included: a frameshift mutation in exon 4 (c.684_685insG) at codon 229 (index patient A); a frameshift mutation in exon 8 (c.1160_1170dupAGGAGCGGCCG) involving codons 387-390 (index patient B); and a missense mutation in exon 4 (c.776T > C), which substitutes leucine with proline at codon 259 (L259P) (index patient C). In the fourth index patient, a common polymorphism (D418D) was detected.


CONCLUSIONS
This is the first report to reveal a high prevalence of novel MEN1 gene mutations among Greek MEN1 patients with apparent absence of genotype-phenotype correlation. Because of the small number of patients examined, the high prevalence detected might be a chance phenomenon.
Second Department of Internal Medicine-Propaedeutic, Research Institute and Diabetes Center, Athens University Medical School, Attikon University Hospital, Athens, Greece. molypepa@otenet.gr
Melpomeni
M
Peppa
Eleni
E
Boutati
Smaragda
S
Kamakari
Vasilios
V
Pikounis
Georgios
G
Peros
Georgios
G
Koutsodontis
Vassiliki
V
Metaxa-Mariatou
Theofanis
T
Economopoulos
Sotirios A
SA
Raptis
Dimitrios
D
Hadjidakis
D000328:Adult; D000368:Aged; D004252:DNA Mutational Analysis; D005260:Female; D016368:Frameshift Mutation; D018095:Germ-Line Mutation; D006115:Greece; D006801:Humans; D008297:Male; D008875:Middle Aged; D018761:Multiple Endocrine Neoplasia Type 1 / Q000235:genetics*; D020125:Mutation, Missense; D010375:Pedigree; D011110:Polymorphism, Genetic; D044465:White People / Q000235:genetics