A Japanese patient with Li-Fraumeni syndrome who had nine primary malignancies associated with a germline mutation of the p53 tumor-suppressor gene.

We describe a patient who had nine primary malignant tumors and a germline mutation in the p53 tumor-suppressor gene, characteristically found in the Li-Fraumeni syndrome (LFS). A 15-year-old girl with no family history of cancer was referred to our hospital because of pain and swelling of the right knee. Osteosarcoma was diagnosed. The patient received chemotherapy followed by surgery and had a remission. After the age of 28 years, nine primary malignant tumors developed successively, including right breast cancer, colon cancer, malignant fibrous histiocytoma (MFH) of the abdominal wall, right lung double cancers, bilateral breast cancers, and MFH of the left thigh. This is the second highest number of types of primary malignant tumors to be reported in LFS. All tumors were treated by a multidisciplinary approach, including surgery. Genetic analysis revealed a germline missense mutation in the p53 gene (c.659 A > G), resulting in Y220C, which has been reported in three families with LFS. The patient died of lung metastasis from MFH at the age of 37 years. Despite the multiple tumors, repeated induction of remissions resulted in long survival. Our findings suggest that a multidisciplinary approach to treatment, including surgery, is beneficial in patients with LFS.

Comprehensive screening of multiple epiphyseal dysplasia mutations in Japanese population.

Multiple epiphyseal dysplasia (MED) is among the most genetically heterogeneous skeletal dysplasias. Six genes involved in MED, COMP, MATN3, COL9A1, COL9A2, COL9A3, and DTDST have been identified; however, the presence of additional disease genes has been reported, and the detection rate for mutations in known genes accounts for no more than 50% of patients with MED in Western populations. Here, we screened the six known disease genes in 35 consecutive Japanese MED patients. We analyzed the entire coding region of each gene, along with flanking intron-exon junctions, by direct sequencing. A total of 19 mutations were identified in COMP, MATN3, COL9A2, COL9A3, and DTDST. The detection rate for known mutations was higher in this study than in previous reports, and we identified a substantially different spectrum of mutations. Mutations in MATN3 were more prevalent among these Japanese patients, whereas no DTDST mutations were detected. Most of the mutations were localized within specific regions of each gene: COMP mutations were found in the calmodulin-like repeat domains; MATN3 mutations in the von Willebrand factor type A domain; and type IX collagen gene mutations occurred in the third collagenous domains. Based on the integration of clinical and genetic information, we propose an algorithm for detecting mutations in Japanese MED patients. Our study further supports the existence of additional MED gene(s).

[Gene testing of hereditary cancer on comprehensive gene medical examination support system].

It has been estimated that genetic factors or a combination of genetic and environmental factors play a role in the development of 10-15% of all cancers. A genetic cause of hereditary cancer has been identified in more than 40 diseases till now. For preventing this cancer, gene testing is essential because it has no definite clinical marker as in hereditary non-polyposis colorectal cancer: HNPCC. Much more experience must be accumulated in this testing at the clinical base in order to increase specificity and sensitivity while safeguarding ethical, legal and social issues (ELSI). Recently, the Personal Information Protection Law was enforced. Gene inspection involving hereditary cancer should be carried out under a comprehensive gene medical examination organization. It is important for the family doctor, medical specialist, and gene inspection person in charge to cooperate closely with one another, and this will be a subject of future study.

The phenotypic spectrum of COL2A1 mutations.

Heterozygous mutations of COL2A1 create several clinical entities collectively termed type II collagenopathies. These disorders not only impair skeletal growth but also cause ocular and otolaryngological abnormalities. The classical phenotypes include the spondyloepiphyseal dysplasia (SED) spectrum with variable severity, Stickler dysplasia type I (STD-I), and Kniest dysplasia (KND). Most COL2A1 mutations occur in the triple helical region of alpha 1(II) chains: the SED spectrum is mostly attributed to missense mutations that substitute bulky amino acids for glycine residues, STD-I to haploinsufficiency of truncation mutations, and KND to exon skipping due to splice-site mutations. To further elucidate the genotype-phenotype relationship of type II collagenopathies, we examined COL2A1 mutations in 56 families that were suspected of having type II collagenopathies, and found 38 mutations in 41 families. Phenotypes for all 22 missense mutations and one in-frame deletion in the triple helical region fell along the SED spectrum. Glycine to serine substitutions resulted in alternating zones that produce severer and milder skeletal phenotypes. Glycine to nonserine residue substitutions exclusively created more severe phenotypes. The gradient of the SED spectrum did not necessarily correlate with the occurrence of extraskeletal manifestations. All nine truncation or splice-site mutations in the triple helical or N-propeptide region caused STD-I or KND, and extraskeletal changes were inevitable in both phenotypes. All six C-propeptide mutations produced a range of atypical skeletal phenotypes and created ocular, but not otolaryngological, changes.

[The RET gene in multiple endocrine neoplasia type 2 (MEN 2)].

Multiple endocrine neoplasia types 2A and 2B(MEN 2A and MEN 2B), and familial medullary thyroid carcinoma(FMTC) are autosomal, dominantly inherited syndromes involving endocrine tumors. MEN 2A is characterized by medullary thyroid carcinoma(MTC), pheochromocytoma(pheo), and parathyroid hyperplasia; MEN 2B is characterized by MTC, pheo, mucosal ganglioneuroma, and marfanoid habitus. Affected individuals in FMTC families develop MTC without any other abnormalities. MEN 2A and MEN 2B and FMTC are caused by germline mutations in the RET proto-oncogene. To investigate the spectrum of RET mutations among Japanese patients, we analyzed the RET gene 118 patients with MEN 2 or FMTC.

[Alteration of the K-ras and p16/CDKN2 gene in endocrine pancreatic carcinomas].

There are many observation of genetic alterations in pancreatic carcinoma. Mutation of codon 12 of K-ras gene relating to cell growth signaling was reported as high as 90%, and p16/CDKN2 gene regulating cell cycle are frequently altered by point mutation, homozygous deletion, or methylation in pancreatic carcinoma. Mutations of K-ras and p16 gene in endocrine pancreatic carcinomas were reported 15-58% in insulinomas or gastrinomas. The alterations of K-ras and p16 gene was detected early event of carcinogenesis, to detect of the alteration with high sensitivity in pancreatic juice and serum, therefore, these alterations are very important for the early diagnosis of endocrine pancreatic carcinomas.

Novel germline hMSH2 genomic deletion and somatic hMSH2 mutations in a hereditary nonpolyposis colorectal cancer family.

Germline and somatic mutations of the hMSH2 gene were determined in a Japanese hereditary nonpolyposis colorectal cancer (HNPCC) family fulfilling the Amsterdam criteria. PCR-SSCP-sequencing of genomic DNA detected a somatic hMSH2 mutation of an A deletion at codon 227-229 in a duodenal carcinoma and a somatic hMSH2 mutation of an A insertion at codon 21 in a gastric carcinoma from affected family members, both carcinomas exhibiting high microsatellite instability. However, no germline hMSH2 mutation was detected by the PCR-SSCP-sequencing method. Genomic DNA was then analyzed by Southern blot hybridization using three hMSH2 cDNA probes (probe A involving exons 1-5, probe B involving exons 4-11 and probe C involving exons 9-16) after digestion by restriction enzymes, EcoRI, HindIII and NsiI. The NsiI digest of DNA from normal tissues of affected members exhibited an aberrant 8.6 kb restriction fragment, in addition to the normal 10.6 kb fragment, when hybridized to probes A and B. This suggested the presence of a heterozygous 2kb genomic deletion encompassing exon 4, 5 or 6. RT-PCR-sequencing revealed that the deleted region encompassed exon 5. This novel genomic deletion of the hMSH2 gene was confirmed to be pathogenic, and the Southern hybridization pattern was applied to the pre-symptomatic diagnosis.

Spondyloepiphyseal dysplasia Maroteaux type: report of three patients from two families and exclusion of type II collagen defects.

Spondyloepiphyseal dysplasia (SED) Maroteaux type is an autosomal dominant skeletal dysplasia, characterized by spondylar dysplasia, mild epiphyseal dysplasia of the large joints, and type E-like brachydactyly. These manifestations overlap with those of spondyloperipheral dysplasia (SPD), in which a sporadic case with a mutation of COL2A1 has been reported. We report on three patients (an affected woman and her son and a sporadic case of an affected man) with SED Maroteaux type. The affected adults were severely short along with stubby hands and feet, and one developed myelopathy as a result of thoracolumbar gibbus. The affected child was mildly short at birth, and developed brachydactyly in early childhood. The radiological hallmarks of these patients included severe platyspondyly with square-shaped vertebral bodies, iliac hypoplasia, epiphyseal hypoplasia of the large joints, and strikingly short metacarpals and phalanges. These radiological findings appeared already apparent in early childhood. SED Maroteaux type was radiologically discriminative from SPD. Brachydactyly was much severe in the former than in the latter, and spondylar dysplasia manifestation was different between both disorders. Mutation screen by polymerase chain reaction-direct sequencing for all exons and their flanking regions of COL2A1 did not reveal any mutations in the three patients.

Novel germline mutation of the PTEN gene in a Japanese family with Cowden disease.

We report a novel germline mutation of the PTEN gene in a Japanese family with Cowden disease. A 46-year-old Japanese man and his mother were diagnosed as having Cowden disease. Their physical examinations revealed multiple facial trichilemmoma, oral mucosal papillomatosis, palmoplantar keratosis, and gastrointestinal polyposis. The single-strand conformation polymorphism (SSCP) analysis showed an abnormal band on exon 7 of their PTEN gene. Direct sequence analysis of exon 7 detected a TAAA insertion to codon 221, producing a stop codon (c.663ins TAAA).

Skewed X-chromosome inactivation causes intra-familial phenotypic variation of an EBP mutation in a family with X-linked dominant chondrodysplasia punctata.

X-linked dominant chondrodysplasia punctata (CDPX2) is a skeletal dysplasia characterized by stippled epiphyses, cataracts, alopecia and skin lesions, including ichthyosis. CDPX2 exhibits a number of perplexing clinical features, such as intra- and inter-familial variation, anticipation, incomplete penetrance and possible gonadal and somatic mosaicism. Recently, mutations in the gene encoding Delta8,Delta7 sterol isomerase/emopamil-binding protein (EBP) have been identified in CDPX2. To better understand the genetics of CDPX2, we examined the entire EBP gene by direct sequencing in four CDPX2 patients. We found EBP mutations in all four patients, including three novel mutations: IVS3+1G>A, Y165C and W82C. Surprisingly, a known mutation (R147H) was identified in a patient and her clinically unaffected mother. Expression analysis revealed the mutant allele was predominantly expressed in the patient, while both alleles were expressed in the mother. Methylation analysis revealed that the wild-type allele was predominantly inactivated in the patient, while the mutated allele was predominantly inactivated in her mother. Thus, differences in expression of the mutated allele caused by skewed X-chromosome inactivation produced the diverse phenotypes within the family. Our findings could explain some of the perplexing features of CDPX2. The possibility that an apparently normal parent is a carrier should be considered when examining seemingly sporadic cases and providing genetic counseling to CDPX2 families.

Familial central diabetes insipidus detected by nocturnal enuresis.

A 10-year-old male referred to our clinic with the chief complaint of nocturnal enuresis also complained of daytime polyuria, frequency, and polydipsia. The clinical diagnosis was central diabetes insipidus. Since the patient's father had complained of similar symptoms, the arginine vasopressin-neurophysin II gene was examined. This revealed a single base substitution in one of two alleles in the patient, his father, and his grandfather (a C to T transition at nucleotide position 280 at codon 19 in the first exon). In conclusion, a history of polyuria or polydipsia should be carefully noted and the urinary volume and urine gravity or osmolarity examined in cases of nocturnal enuresis.

One-step PCR to distinguish B virus from related primate alphaherpesviruses.

By adding betaine to the PCR mixture, we previously established a PCR method to amplify a DNA segment of the glycoprotein G gene of B virus (BV) derived from a rhesus macaque. We have found that DNA of other BV strains derived from cynomolgus, pigtail, and lion-tailed macaques can also serve as the template in our PCR assay. Under the same conditions no product was obtained with DNA of simian agent 8 of green monkeys and Herpesvirus papio 2 of baboons, or the human herpes simplex viruses types 1 and 2. Thus, this PCR method is useful to discriminate BV from other closely related primate alphaherpesviruses.