OBJECTIVETo investigate the role of loss of heterozygosity (LOH) in tumor suppressor genes (TSG) and microsatellite instability (MSI) in hepatocarcinogenesis, as well as their correlation with clinicopathologic features.

METHODSLOH in 6 TSG (APC, DCC, MCC, OGG1, p53 and RB1) was detected in 36 informative cases of hepatocellular carcinoma (HCC), among 92 surgically resected HCC. Thirteen polymorphic microsatellite markers were also studied in 15 of these cases by microdissection-based PCR amplification and direct DNA sequencing. The correlation between genetic alterations and clinicopathologic features was analyzed.

RESULTSThe overall incidence of LOH in HCC was 41.7% (15/36). There was no LOH in MCC gene. 46.2% (6/13) microsatellites showed LOH in 9 of the 15 cases of HCC (60%). Certain clinicopathologic differences were observed between cases (number = 7) with LOH in APC, OGG1 and DCC ("type I") and cases (number = 8) with LOH in p53 and RB1 ("type II"). The mean tumor size of these two types was 2.9 (+/- 1.7) cm and 7.2 (+/- 3.4) cm, respectively (P < 0.01); and the mean survival was 72.0 (+/- 38.6) months, and 51.0 (+/- 30.4) months, respectively (P < 0.05).

CONCLUSIONSCompared with MSI pathway, LOH pathway plays a more important role in the development of HCC. A multistep hepatocarcinogenesis is likely, with LOH in APC, OGG1 and DCC ("type I") being an early event and LOH in p53 and RB1 ("type II") being a late event. On the other hand, MCC gene seems to play no role in the whole process.

Adult ; Aged ; Aged, 80 and over ; Carcinoma, Hepatocellular ; genetics ; pathology ; Female ; Genes, APC ; Genes, DCC ; Genes, MCC ; Genes, Tumor Suppressor ; Genes, p53 ; Humans ; Infant ; Liver Neoplasms ; genetics ; pathology ; Loss of Heterozygosity ; Male ; Microsatellite Instability ; Middle Aged

Autosomal recessive cerebellar ataxias (ARCA) are a highly heterogeneous group of rare neurodegenerative diseases affecting both central and peripheral nervous systems. Based on pathological mechanisms, five major types of ARCA may be distinguished, which include mitochondrial ataxia, metabolic disorder, DNA repair defect ataxia, congenital ataxias and degenerative ataxia. This review summarizes clinical features, molecular genetics and recent advances in DNA sequencing of common types of ARCA.
Cerebellar Ataxia ; classification ; genetics ; metabolism ; Genes, Recessive ; Humans

Genes, Recessive ; Humans ; Nephritis, Hereditary ; diagnosis ; Nephrotic Syndrome ; diagnosis

Ectodermal dysplasia tends to fall into two groups, the hidrotic and anhidrotic fo rms. Each type has a seperate geneologic origin and distinct clinical manifestation. The hidrotic form usually results from the action of an autosomal dominant gene, whereas the anhidrotic form appears to be deterrnined by the action of a sex linked recessive gene. In the hidrotic form the main clinical manifestations are dystrophic nails, defects of hair shaft and hyperkeratosis of the palms and soles. Recently one case with dystrophic nails, defects of hair and eyebrow and normaI sweating function without family history has been seen by us.
Ectoderm* ; Ectodermal Dysplasia ; Eyebrows ; Genes, Dominant ; Genes, Recessive ; Hair ; Humans ; Sweat ; Sweating

Development of the human colorectal cancer is associated with several distinct genetic abnormalities involving both dominant-acting oncogenes (K-ras, c-src) and tumor suppressor genes (APC, DCC, p53) which undergo inactivation or loss. In colorectal tumors, the common molecular alteration is localized in the 17p13 and 5q21 loci encoding the p53 and the APC gene, respectively. The identification of these genes may help the understanding of the pathogenesis of colorectal neoplasia. In order to determine whether the frequency of the genetic alterations varies with sex, age, tumor size, or site, including pathologic parameters, such as degree of differentiation, tumor stage, mucin component, lymphoid reaction, tumor invasion pattern, vein and nerve invasion, lymph node metastasis, and other parameters, such as disease-free survival, distant metastasis and patient outcome, the authors analyzed the loss of heterozygosity (LOH) of the APC and the p53 genes in paraffin-embedded specimens of 48 colorectal cancers by use of the polymerase chain reaction and restriction fragment length polymorphism. The results were as follows: the LOH affecting the APC was found in 15 out of 31 (48.4%) heterozygous patients, while the LOH of the p53 locus was observed in 11 out of 26 (42.3%) patients. Among 48 patients, the LOH at both the APC and the p53 loci was observed in five (10.4%) patient. No statistically significant associations were found between the LOH of the APC gene and the proposed parameters. The relationship between the LOH of the p53 and the histologic differentiation, lymphoid reaction was significant (P<0.05), but survival was not correlated. Statistically significant associations were found between overall survival of the colorectal cancer patients and distant metastasis, Astler-Coller stage, lymphoid reaction, invasion pattern, nerve invasion, vein invasion, lymph node metastasis, and disease free survival. The above results suggest that the LOH of the p53 genes could be involved in the progression of colorectal cancers. However, neither the LOH of the APC nor that of the p53 have significant association with survival of the colorectal cancer patients.
Colorectal Neoplasms* ; Disease-Free Survival ; Genes, APC ; Genes, p53 ; Genes, Tumor Suppressor* ; Humans ; Loss of Heterozygosity* ; Lymph Nodes ; Mucins ; Neoplasm Metastasis ; Oncogenes ; Polymerase Chain Reaction ; Polymorphism, Restriction Fragment Length ; Veins

The faded mouse is a coat color mutant that shows faded coat color and age-related loss of pigmentation. This mutation is transmitted by an autosomal recessive gene with 100% penetrance. In the present study, we carried out linkage analysis of the faded (fe) gene using intra-specific backcross panels. Affected faded mice were carefully confirmed by their faded coat color at about 4 weeks of age. In the intra-specific backcross between faded and CBA mice (n=198), the fe gene was mapped to a region 2.1 cM distal to D10mit191. Therefore, the gene order was defined as follows: centromere-D10mit51 (12.4+/-2.4 cM)-D10mit191 (2.1+/-1.0 cM)-fe-D10mit44 (13.3+/-2.4 cM)-D10mit42 (14.4+/-2.5 cM). This linkage map of the fe locus will provide a good entry point to isolate the fe gene. Since the faded mouse has pigmentary abnormalities, this mutant may be a useful model for studies of pigmentary abnormalities in humans.
Animals ; Chromosomes, Human, Pair 10 ; Gene Order ; Genes, Recessive ; Humans ; Mice ; Mice, Inbred CBA ; Penetrance ; Pigmentation

Introduced in 2009, whole-exome sequencing (WES) is a technology in which target capture methods are used to enrich sequences of coding regions of genes from fragmented total genomic DNA, which is followed by high-throughput sequencing of the captured fragments. As reported, WES has been successfully applied for discovering genes underlying several Mendelian diseases, especially autosomal recessive types. In this review, authors have summarized the main computational strategies which have been applied to identify novel autosomal recessive diseases genes using whole-exome data.
Cloning, Molecular ; Exome ; Genes, Recessive ; Genetic Diseases, Inborn ; genetics ; Humans ; Sequence Analysis, DNA

Child ; Ectodermal Dysplasia ; diagnosis ; genetics ; Family Health ; Genes, Recessive ; genetics ; Humans ; Male ; Sex Factors

Attractin, the research of which has flourished in recent years, is an autosomal recessive gene. The gene is widely expressed, and involved in a number of physiological and pathological events. This paper reviews the research development of the Attractin gene, including the characterization, expression, mutation, function and molecular mechanism of this gene. Besides, further research on the gene is also suggested.
Animals ; Gene Expression ; Genes, Recessive ; Humans ; Male ; Membrane Proteins ; genetics ; Molecular Sequence Data ; Mutation ; Rats

OBJECTIVETo analyze the clinical features and gene mutation of Chinese children with Alport syndrome(AS).

METHODFrom May 2011 to May 2014, clinical and pathological information gathered from 25 patients was retrospectively analyzed. COL4A5, COL4A4 and COL4A3 genes were analyzed using next-generation sequencing in these patients, and gene mutations of related family members were identified by Sanger method.

RESULTOf these 25 cases, 19(76%) had X-linked Alport syndromes (XL-AS), 6 had autosomal recessive Alport syndromes (AR-AS). Twenty five patients had an onset of hematuria and proteinuria and in 8 cases the disease was induced by upper respiratory tract infections. Hearing loss was present in 2 of 25 (8%) cases and ocular lesions in 1 of 25 (4%). Renal pathology showed that 16 of them had minimal change disease (MCD), 8 mesangial proliferative glomerulonephritis (MsPNG), 1 focal segmental glomerulo-sclerosis (FSGS). Extensive lamination and split of glomerular basement membrane (GBM) dense layers were found in 2 (8%) of 25 patients. Twenty one of 25 patients (84%) showed abnormal renal α-chain distribution. COL4A5, COL4A4 and COL4A3 genes of 25 patients (23 families) were analyzed and 24 pathogenic mutations were identified: 18 in COL4A5, 1 in COL4A3 and 5 in COL4A4. It was observed that 13 patients inherited the mutation from the mother, 3 patients inherited from the father, 2 patients inherited 1 mutation from the mother and another mutation from the father, and 7 patients carried the novel mutations.

CONCLUSIONXL is the main inherited type in AS. Most of patients showed MCD and MsPNG in renal biopsy. This research examined 24 mutations and 16 mutations were not reported previously.

Child ; Deafness ; Genes, Recessive ; Genotype ; Hematuria ; Humans ; Kidney ; Mutation ; Nephritis, Hereditary ; genetics ; pathology ; Pedigree ; Phenotype