Inheritance of ornithine aminotransferase gene, mRNA, and enzyme defect in a family with gyrate atrophy of the choroid and retina.

We studied the human ornithine aminotransferase (OAT) gene, mRNA, and enzyme activity in fibroblasts from a family with gyrate atrophy (G.A.) of the choroid and retina, using a normal human OAT cDNA as a probe. The family consists of an affected patient, who is heterozygous for a partial deletion of the functional OAT gene and whose cells produce no mRNA, and of his father, mother, two sons, and a daughter. Southern blot analysis of the OAT gene showed the partial deletion in the patient and in his father and daughter and in one son. Northern blot analysis revealed no OAT mRNA in the patient and approximately 50% of the normal level of OAT mRNA in the father, mother, two sons, and daughter. Assay showed that the OAT activity in these individuals mirrored the OAT mRNA levels. The results indicate that an active allele of the OAT gene expresses 50% of the total normal OAT mRNA and activity and that both alleles of the gene are inactive in the patient in this pedigree, a situation resulting in a complete absence of the OAT mRNA, in accordance with the autosomal recessive mechanism of this disease; they also indicate a 50% decrease of OAT mRNA and enzyme activity in obligate heterozygous carriers carrying one defective allele and that these defects are stably inherited.     

G6PD lozere and trinacria-like

Summary Two new G6PD variants have been found in red blood cells of the members of a French family originating from Lozere. The father is hemizygous for an electrophoretically fast variant with mild enzyme deficiency (50–60% of normal). The abnormal paternal G6PD gene is segregating in his daughter who is double heterozygous for maternal and paternal variants. This mutant enzyme, different from previously described variants is designated as Gd Lozère. The mother is heterozygous for another G6PD variant. Two sons are hemizygous for this latter mutant enzyme characterized by a moderate deficiency (25–30% of normal) and slower electrophoretic mobility with some slightly altered kinetic properties. This G6PD has been identified as Gd Trinacria like.These two abnormal enzymes are not associated with any hemolytic problem. Case reported is the first showing the segregation of two new mutant enzymes, distinct from common G6PD variants, among the members of the same family.     

Histochemical demonstration of acetylcholinesterase in sporocysts of Schistosoma mansoni (Trematoda).

The distribution of acetylcholinesterase in mother and daughter sporocysts of Schistosoma mansoni was studied histochemically. In young mother sporocysts derived from miracidia cultured in vitro the miracidial neural mass and flame cells were shown to persist. The nerve trunks and commissures, as well as papillae, are apparently lost in the transformation process. In young daughter sporocysts freshly dissected from mother sporocysts there was little enzyme activity except for a sparse distribution in the tegument. After cultivation, intense enzyme activity was associated with developing cercarial embryos. A similar distribution of activity was observed in older daughter sporocysts obtained from the digestive gland of snails. No evidence of flame cells, neural mass, or commissures was detected in daughter sporocysts by the methods employed.     

An unusual case of blood group ABO inheritance: O from AB X O

An unusual blood group inheritance, that is, a phenotype O child from AB X O parents, was found in a Japanese family. Since two other children from the parents are blood type B, this is not a case of Cis-AB inheritance. The mother is not blood A/B chimera, and normal levels of blood group N-acetylgalactosaminyltransferase (A-enzyme) and galactosyltransferase (B-enzyme) were detected in her plasma. Therefore, the mother is genetically true AB heterozygous. The two sons with phenotype B had normal levels of plasma B-enzyme, but had no A-enzyme, and the father and the daughter with phenotype O had neither A- nor B-enzyme in their plasma. The analyses of 24 genetic marker systems indicated that the O daughter was a true child of the parents. The affirmative probability of parentage on the O daughter was calculated to be .9999999917 by Bayes' theorem. We concluded that the genotype of the O daughter was not the usual 00, and that this rare O expression might be due to a new structural mutation or a deletion in either maternal A or B gene during oogenesis.     

Micro-array analyses decipher exceptional complex familial chromosomal rearrangement

Recently there has been an increased interest in large-scale genomic variation and clinically in the consequences of haploinsufficiency of genomic segments or disruption of normal gene function by chromosome rearrangements. Here, we present an extraordinary case in which both mother and daughter presented with unexpected chromosomal rearrangement complexity, which we characterized with array-CGH, array painting and multicolor large insert clone hybridizations. We found the same 12 breakpoints involving four chromosomes in both mother and daughter. In addition, the daughter inherited a microdeletion from her father. We mapped all breakpoints to the resolution level of breakpoint spanning clones. Genes were found within 7 of the 12 breakpoint regions, some of which were disrupted by the chromosome rearrangement. One of the rearrangements disrupted a locus, which has been discussed as a quantitative trait locus for fetal hemoglobin expression in adults. Interestingly, both mother and daughter show persistent fetal hemoglobin levels. We detail the most complicated familial complex chromosomal rearrangement reported to date and thus an extreme example of inheritance of chromosomal rearrangements without error in meiotic segregation. Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.     

Are increased individual susceptibility and environmental factors both necessary for the development of primary biliary cirrhosis?

A daughter, her mother, and an unrelated close friend developed primary biliary cirrhosis (PBC). The mother and the close friend nursed the daughter through her terminal illness and presented with PBC PBC within 21 months after her death. Half of the asymptomatic first-degree relatives in the two families had serum autoantibodies, including one with antimitochondrial antibody, suggesting some genetic susceptibility to abnormal immune reactions. It is concluded that some environmental factor may be present in PBC, perhaps in addition to a genetic susceptibility to that factor.     

Apparent regression of the CGG repeat in FMR1 to an allele of normal size

The fragile X syndrome is the result of amplification of a CGG trinucleotide repeat in the FMR1 gene and anticipation in this disease is caused by an intergenerational expansion of this repeat. Although regression of a CGG repeat in the premutation range is not uncommon, regression from a full premutation (>200 repeats) or premutation range (50–200 repeats) to a repeat of normal size (<50 repeats) has not yet been documented. We present here a family in which the number of repeats apparently regressed from approximately 110 in the mother to 44 in her daughter. Although the CGG repeat of the daughter is in the normal range, she is a carrier of the fragile X mutation based upon the segregation pattern of Xq27 markers flanking FMR1. It is unclear, however, whether this allele of 44 repeats will be stably transmitted, as the daughter has as yet no progeny. Nevertheless, the size range between normal alleles and premutation alleles overlap, a factor that complicates genetic counseling.     

Reaction of antibody to normal human hypoxanthine phosphoribosyltransferase with products of mutant genes.

Immunoglobulin produced in rabbits against normal human red cell hypoxanthine phosphoribosyl transferase (HPRT, EC 2.4.2.8) was used to study cell lysates of individuals with deficient enzyme activity. The reaction of immunoglobulin with HPRT formed partially active insoluble and fully active soluble complexes. The insoluble complexes were separated from soluble complexes and the free enzyme by centrifugation. The soluble complexes and free enzyme were separated by electrophoresis. Hemolysates from 13 patients with the Lesch-Nyhan syndrome who have virtually total deficiency of HPRT activity and 2 patients with hyperuricemia and 2–5% of normal activity were unable to neutralize immunoglobulin and showed no evidence of cross-reacting material (CRM). In contrast, 2 other partially deficient males with 4.5 and 50% of normal actvity, and a partially deficient heterozygous female with 34% of normal activity, were CRM⁺ in this assay. The amount of CRM present in the cells of these 2 males appeared to be disproportionate to their HPRT activity. The heterozygous female contained about 30% of normal CRM which was consistent with the estimated activity provided by her normal cell population. This indicated that her abnormal cells were CRM^?. Absence of CRM in her abnormal cells was consistent with the observed lack of CRM in hemolysates of her hyperuricemic half-brother. These data indicate the presence of considerable heterogeneity in human mutation at the HPRT locus.     

Activities of branched-chain 2-oxo acid dehydrogenase and its components in skin fibroblasts from normal and classical-maple-syrup-urine-disease subjects.

1. Comparisons of the activity and kinetics of the branched-chain 2-oxo acid dehydrogenase in cultured skin fibroblasts from normal and classical maple-syrup-urine-disease (MSUD) subjects provide a kinetic explanation for the enzyme defect. 2. In the intact cell assays, normal fibroblasts demonstrated hyperbolic kinetics with 3-methyl-2-oxo[1-14C]butyrate as a substrate. Intact fibroblasts from four classical MSUD patients showed no decarboxylation over a substrate concentration range of 0.25 to 5.0 mM, and thiamin (4 mM) was without effect. 3. The overall reaction of the multienzyme complex was efficiently reconstituted by using a disrupted-cell system. Normals again showed typical hyperbolic kinetics at the 2-oxo acid concentrations of 0.1 to 5 mM. The Vmax. and apparent Km values were 0.10 +/- 0.02 m-unit/mg of protein and 0.05-0.1 mM respectively, with 3-methyl-2-oxobutyrate. In contrast, classical MSUD patients exhibited sigmoidal kinetics (Hill coefficient, 2.5) with activity approaching 40-60% of the normal value at 5 mM substrate. The K0.5 values from the Hill plots for MSUD patients were 4-7 mM. 4. The E1 (branched-chain 2-oxo acid decarboxylase) component of the multienzyme complex was measured in disrupted-particulate preparations. Normals again showed hyperbolic kinetics with the 2-oxo acid, whereas MSUD preparations exhibited sigmoidal kinetics with the activity of E1 strictly dependent on substrate concentration. Apparent Km or K0.5 were 0.1 and 1.0 mM for normal and MSUD subjects respectively. 5. Measurements of E2 (dihydrolipoyl transacylase) and E3 (dihydrolipoyl dehydrogenase) in MSUD preparations showed them to be in the normal range. 6. The above data suggest a defect in the E1 step of branched-chain 2-oxo acid dehydrogenase in classical MSUD patients.     

Familial occurrence of typical and severe lethal congenital contractural arachnodactyly caused by missplicing of exon 34 of fibrillin-2.

Genetic linkage studies have linked congenital contractural arachnodactyly (CCA), a usually mild heritable connective-tissue disorder, to FBN2, the fibrillin gene on chromosome 5. Recently, FBN2 mutations in two patients with CCA have been described. Here we report an A-->T transversion at the -2 position of the consensus acceptor splice site, resulting in the missplicing of exon 34, a calcium-binding epidermal growth factor-like repeat in fibrillin-2 in a mother and daughter with CCA. Significantly, the mother exhibited a classic CCA phenotype with arachnodactyly, joint contractures, and abnormal pinnae, whereas her daughter exhibited a markedly more severe CCA phenotype, which included cardiovascular and gastrointestinal anomalies that led to death in infancy. Analysis of cloned fibroblasts showed that the mother is a somatic mosaic for the exon 34 missplicing mutation, whereas all the daughter''s cells harbored the mutation.     

Glucose phosphate isomerase deficiency with hereditary hemolytic anemia in a Spanish family: clinical and familial studies.

A new case of glucose phosphate isomerase deficiency associated with cogenital nonspherocytic hemolytic anemia is described in a 12-year-old girl of Spanish origin. The parents exhibited erythrocyte glucose phosphate isomerase activity between 50 and 60% of normal. The enzyme of the propositus had normal Michaelis-Menten constants both for F-6-P and G-6-P, but abnormal pH optimum and decreased heat stability at 48 degrees C. On starch-gel electrophoresis the father's enzyme was normal but the mother's showed a cathodic migrating band in addition to the normal one. The enzyme from the propositus exhibited only one band with cathodal mobility of 116% of the main band found in normal subjects. It is postulated that the propositus is double heterozygous for two abnormal alleles, and the mother contributes a mutant allele with abnormal electrophoretic mobility and thermolability at 48 degrees C whereas the father contributes an allele without enzymatic activity.     

Familial cylindromatosis

Familial cylindromatosis: we report a daughter with turban tumor and her mother with cylindromatosis. The dermal eccrine cylindroma arose as small, solitary lesions on the head of the mother when she was 28 years old. The following years other tumors became apparent. She was operated on several times. The first lesions appeared on the frontal part of the scalp of the daughter when she was 23 years old. Other tumors grew on the scalp. Histopathological examination of the excised tumors showed the same lesions in both the mother and the daughter: dermal eccrine cylindromata. Family history showed that the daughter's maternal aunt had a few tumors. Dermal eccrine cylindroma should be differentiated from malignant syndromes such as basal naevoid carcinoma or metastases and from neurofibromata. The gene of familial cylindromatosis was localised to chromosome 16q12-q13 and it was proposed that this gene is a tumor supressor gene.     

Social Behaviour of the Carpenter Bee Xylocopa pubescens (Spinola)

The development of about 20 relatively small nests of Xylocopa pubescens was studied. After the first offspring had become adult, these nests reached a social stage in which there was only one egg-layer per nest. Freshly emerged (teneral) adults eat a lot of food, collected by a forager, before they fly out of the nest. This food appears to be of major importance to these bees in that it makes them fully agile. It seems therefore, that part of the food needed for the development of a young bee is not given at the larval stage, via the beebread, but at the teneral adult stage. As a result of this, a necessary overlap of generations is accomplished. Besides, less pollen has to be collected for the provision of a brood cell, so more cells can be constructed within a short period of time. There is a high degree of nest competition. Many nests were taken over by conspecific individuals (or by females of X. sulcatipes) that were searching for nesting sites within the study area. However, although more than 50% of the solitary nests were taken over sooner or later, strangers hardly ever intruded into social nests, with more than one adult. This illustrates how important it is for a reproducing female to tolerate the presence of nestmates which guard the nest in her absence. Although in most cases the foundress of a nest proceeded to produce new brood in the presence of her offspring, it happened that a daughter took over reproduction from her mother. In two of these cases, it could be observed that a mother started a new nest elsewhere after having been thrown out by her own daughter. At least in these cases, nest competition between mother and daughter started long before the mother had reached the end of her reproductive capacities. Since nesting possibilities are scarce, it seems a logical strategy to stay in the maternal nest and wait for a chance to become the egg-layer if the mother dies or if she loses her dominance. The occurrence of several social interactions among nestmates is discussed: — trophallaxis was observed often, not only under ‘forced’ conditions, but also as a form of ‘voluntary’ feeding; — nestmates were observed to groom each other.     

Biochemical and genetic characterization of the DNA ligase encoded by Saccharomyces cerevisiae open reading frame YOR005c, a homolog of mammalian DNA ligase IV.

Here we demonstrate that the Saccharomyces cerevisiae DNA ligase activity, which we previously designated DNA ligase II, is encoded by the genomic DNA sequence YOR005c. Based on its homology with mammalian LIG4, this yeast gene has been named DNL4 and the enzyme activity renamed Dnl4. In agreement with others, we find that DNL4 is not required for vegetative growth but is involved in the repair of DNA double-strand breaks by non-homologous end joining. In contrast to a previous report, we find that a dnl4 null mutation has no effect on sporulation efficiency, indicating that Dnl4 is not required for proper meiotic chromosome behavior or subsequent ascosporogenesis in yeast. Disruption of the DNL4 gene in one strain, M1-2B, results in temperature-sensitive vegetative growth. At the restrictive temperature, mutant cells progressively lose viability and accumulate small, nucleated and non-dividing daughter cells which remain attached to the mother cell. This novel temperature-sensitive phenotype is complemented by retransformation with a plasmid-borne DNL4 gene. Thus, we conclude that the abnormal growth of the dnl4 mutant strain is a synthetic phenotype resulting from Dnl4 deficiency in combination with undetermined genetic factors in the M1-2B strain background.     

Skewed inactivation of an X chromosome deleted at the dystrophin gene in an asymptomatic mother and her affected daughter

A girl with severe Becker muscular dystrophy and apparently normal chromosomes had a heterozygous deletion for exons 51, 52, and 53 of the dystrophin gene. This deletion was transmitted by her mother, who was unaffected. To differentiate the normal and the deleted X chromosomes, fluorescence in situ hybridization (FISH) was applied to metaphase chromosomes, using probes for both exons 51 and 52, which are only 388 and 113 base pairs long, respectively. FISH signals were observed in one or both chromatids of one chromosome, but never on both chromosomes, suggesting the lack of hybridization on the deleted X chromosome. Using 5-bromodeoxyuridine incorporation to differentiate the late (inactive) and the early replicating (active) X chromosomes, 77% of the signals were observed on the active X chromosomes in the mother. This percentage was only 18% in the daughter, suggesting that skewed inactivation of the X chromosomes was responsible for the phenotypic differences.     

Galactosemia: a strategy to identify new biochemical phenotypes and molecular genotypes.

We describe a stratagem for identifying new mutations in the galactose-1-phosphate uridyl transferase (GALT) gene. GALT enzyme activity and isoforms were defined in erythrocytes from probands and their first-degree relatives. If the biochemical phenotypes segregated in an autosomal recessive pattern, we screened for common mutations by using multiplex PCR and restriction endonuclease digestions. If common mutant alleles were not present, the 11 exons of the GALT gene were amplified by PCR, and variations from the normal nucleotide sequences were identified by SSCP. The suspected region(s) was then analyzed by direct DNA sequencing. We identified 86 mutant GALT alleles that reduced erythrocyte GALT activity. Seventy-five of these GALT genomes had abnormal SSCP patterns, of which 41 were sequenced, yielding 12 new and 21 previously reported, rare mutations. Among the novel group of 12 new mutations, an unusual biochemical phenotype was found in a family whose newborn proband has classical galactosemia. He had inherited two mutations in cis (N314D-E203K) from his father, whose GALT activity was near normal, and an additional GALT mutation in the splice-acceptor site of intron C (IVSC) from his mother. The substitution of a positively charged E203K mutation created a unique isoform-banding pattern. An asymptomatic sister''s GALT genes carries three mutations (E203K-N314D/N314D) with eight distinct isoform bands. Surprisingly, her erythrocytes have normal GALT activity. We conclude that the synergism of pedigree, biochemical, SSCP, and direct GALT gene analyses is an efficient protocol for identifying new mutations and speculate that E203K and N314D codon changes produce intraallelic complementation when in cis.     

Maternal inheritance of deleted mitochondrial DNA in a family with mitochondrial myopathy

Skeletal muscles from a mother and her daughter both with chronic progressive ophthalmoplegia were analyzed. Histological and biochemical analyses of their muscle samples showed typical features of this type of mitochondrial myopathy. Southern blot analysis revealed that, in both patients, there were two species of mitochondrial DNA (mtDNA): normal one and partially deleted one. The sizes of the deletion were different; the mutant mtDNAs from the mother and the daughter had about 2.5- and 5-kilobase deletions, respectively. The two mutant mtDNAs shared a common deleted region of 1.2-kilobase. However, both the start and the end of deletion were different between them, implying a novel mode of inheritance. This is the first report that the mutant mtDNA is responsible for the maternal inheritance of a human disease.     

一例急性间歇性血卟啉病病例报道及文献回顾

目的:对患有急性间歇性血卟啉病先证者及其两位直系亲属进行基因突变的分析。方法:采用PCR和一代测序技术分别对患者的HMBS基因的外显子及其旁翼区进行序列分析。结果:检测出先证者HMBS基因11号外显子的旁翼区发生杂合突变c.651+2AG,为剪切突变;从先证者母亲以及女儿的HMBS基因上检测出同样的突变位点。结论:根据先证者的家族史、临床表现及相关代谢检查结果诊断为血卟啉病;基因检测结果提示先证者为急性间歇性血卟啉病;先证者的母亲和女儿存在同样的突变位点,提示先证者母亲及其女儿均患有急性间歇性血卟啉病。     

Observation of a wild Japanese macaque mother pacifying her distressed infant with an acorn

This is the first report on an observation of food transfer by a mother to her offspring in wild Japanese macaques (Macaca fuscata yakui). On November 6, 1996, an adult female wild Japanese macaque stopped grooming her 1.5–1.6 yr old daughter in order to be groomed by a young male. Her daughter protested loudly for about 1 min. In response to her daughter's protest, the mother picked up a mature nut ofQuercus phillyraeoides that was lying near her right hand, and placed it in the daughter's mouth. The daughter's cries were immediately muffled and she silently ate the acorn's contents, and spat out the pericarp. We inferred that the daughter wanted to be groomed by her mother, not to receive food. This reported example of treatment resembling tool using behavior in response to an emotional outcry was precipitated by mother-offspring conflict in the natural habitat.     

Expression of ABH and X (Lex) antigens in various cells

Using a panel of reagents specific to the various subtypes of ABH antigens, it could be demonstrated that platelets carry ABH type 2 monofucosylated determinants on intrinsic glycoproteins. The presence of these antigens is controlled by the H gene and correlates with the presence of alpha-2-L-fucosyltransferase and the absence of alpha-3-L-fucosyltransferase. In contrast, intrinsic ABH antigens were not found on mononuclear cells, correlating with the absence of alpha-2-L-fucosyltransferase on these cells. However, after transformation with the Epstein-Barr virus and stimulation with 12-O-tetradecanoylphorbol-13-O-acetate (TPA), B lymphocytes were found to express the H antigen under control of the H gene and not the Se gene. The lymphoblastoid cell lines also expressed the X and sialylated X antigens which are normally markers of the myeloid lineage. These antigens are also normally found in epithelial cells of the digestive tract, kidney proximal convoluted tubules and hepatocytes. The alpha-3-L-fucosyltransferase responsible for the synthesis of this antigen is present in the serum but we report the existence of two individuals, a mother and her daughter, who lack more than 90% of this serum enzyme. The young girl suffers from a congenital kidney anomaly: oligomeganephronic hypoplasia. Her kidney tubules are devoid of X antigen. However, she and her mother have the X antigen on their granulocytes and its sialylated form on their monocytes. It therefore appears that there are distinct genetic controls for the expression of antigen X in different body compartments. This would be quite similar to the H and Se gene controls in tissues of distinct embryological origins.