Search

The effect of cattle breed on stearoyl-CoA desaturase (SCD) gene expression was investigated in this study. Detailed comparisons of SCD mRNA level were made among three steers each of Japanese Black, Holstein and their crossbreed which were age-matched had been fed the same diet and were sampled by biopsy of the longissimus dorsi (LD) muscle and subcutaneous fat. The levels of SCD mRNA were measured in samples of muscle and subcutaneous fat. The levels of SCD mRNA demonstrated a breed effect in each tissue, though the relative expression was higher (P

Summary To understand the relevance of allergy to the development of asthma in children, we examined basophil hislamine release (HR) with Df antigen, blood cosinophii counts, serum eosinophil cationic protein (ECP) levels, and bronchial responsiveness to methacholine (PC20) in three groups of children, including 36 asthmatics with high RAST titre for Df (group 1), 36 non-asthmatics with similarly high RAST titre for Df (group 2) and 21 non-asthmatics with negative RAST titre for Df (group 3). The amount of Df antigen inducing 50% HR from basophils did not vary significantly between group 1 and 2 (P>0.05), while none of the cells responded to higher concentrations of Df in group 3. The mean number of blood eosinophils and level of serum ECP were highest in group 1, and lowest in group 3, with group 2 being intermediate, and the differences were significant between all three groups (P

Primary hypoalphalipoproteinemia is associated with atherosclerosis and exhibits significant familial aggregation. To reveal the presence of autosomal dominant hypoalphalipoproteinemia due to a completely defective apolipoprotein A-I gene, the apolipoprotein A-I gene was analyzed in a Japanese family with low levels of HDL cholesterol and apolipoprotein A-I. An insertion of a C in the region of the seven C run between codons 3 and 5 was detected in the apolipoprotein A-I gene. The heterozygous state for the mutation was associated with approximately 50% of the normal HDL cholesterol levels and of the normal apolipoprotein A-I levels. The data suggest that a part of familial hypoalphalipoproteinemia might be an autosomal dominant trait due to a completely defective apolipoprotein A-I gene.

We describe a Japanese boy with ring chromosome 18 in whom abnormal myelination was observed on magnetic resonance imaging. Cytogenetic investigation revealed 46, XY, r(18) (p11.2 q21.33). T 2- weighted magnetic resonance imaging scan of the brain demonstrated high signal intensity consistent with abnormal myelination. Microsatellite marker analysis of DNA demonstrated only one copy of the myelin basic protein gene, derived from the mother. The present case indicates that a hemizygous state for the myelin protein gene may be related to the abnormal myelination.

Increases in height were reported in children chronically exposed prenatally and postnatally to D2 receptor-blocking drugs. A possible haplotypic association between stature and the DRD2 gene was also reported. In this study, we examined linkage between stature and DRD2 by genotyping a dinucleotide repeat polymorphism in 79 sib-pairs aged 8-17 years. An association between stature and a putative functional polymorphism in the promoter region of the DRD2 gene was examined in the sib-pairs and in 125 unrelated male adults. All the subjects were Japanese. Linkage (p = 0.004, SIBPAL) and an association (p = 0.009, paired t-test, in the sib-pairs; p = 0.006, ANOVA, in the adults) with stature were suggested. These findings indicate that DRD2 is one of the genes that contribute to heritability of stature.

To determine the frequency of familial hypoalphalipoproteinemia in the general population due to mutation of the apolipoprotein A-I (apo A-I) gene, we analyzed sequence variations in the apo A-I gene. The subjects were 67 children with a low high-density lipoprotein (HDL) cholesterol level (

A novel complex mutation with the presence of both deletion and insertion in very close proximity in the same region was detected in exon 8 of the LDL receptor gene from two apparently unrelated Japanese families with familial hypercholesterolemia (FH). In this mutant LDL receptor gene, the nine bases from nucleotide (nt) 1115 to nt 1123 (AGGGTGGCT) were replaced by six different bases (CACTGA), and consequently the four amino acids from codon 351 to 354, Glu-Gly-Gly-Tyr, were replaced by three amino acids, Ala-Leu-Asn, in the conserved amino acid region of the growth factor repeat B of the LDL receptor. The nature of the amino acid substitution and data on the families suggest that this mutation is very likely to affect the LDL receptor function and cause FH. The generation of this complex mutation can be explained by the simultaneous occurrence of deletion and insertion through the formation of a hairpin-loop structure mediated by inverted repeat sequences. This this mutation supports the hypothesis that inverted repeat sequences influence the stability of a given gene and promote human gene mutations.

Our recent data on genes associated with premature coronary heart disease (CHD) or possibly involved in CHD in the Japanese population are described. Frequency distributions, mean values and median values of plasma lipoprotein (a) (Lp(a)) concentrations in a Japanese population are similar to those in most Caucasians. Preliminary data suggest that apolipoprotein (a) is also highly polymorphic in the Japanese population. Furthermore, in inactive plasminogen, phenotype M5, is polymorphic in the Japanese. Data obtained with polymerase chain reaction (PCR) and allele-specific oligonucleotide probes indicate that plasminogen M5 has a codon 601 missense mutation (GCT → ACT, Ala → Thr) and is identical with plasminogen Tochigi. As to apolipoprotein (apo) E polymorphisms, data obtained with PCR and allele-specific oligonucleotide probes suggest that many of apo E-2 have the codon 158 missense mutation (CGC → TGC, Arg → Cys) and that most, if not all, of apo E-4 have the codon 112 missense mutation (TGC → CGC, Cys → Arg) in the Japanese. The frequencies of alleles for apo E-2 and E-4, however, is lower in Japanese than in most Caucasians. As regarding familial hypercholesterolemia (FH), whose heterozygote frequency is estimated to be 1 in 500 persons in the Japanese, data obtained with family studies of the low density lipoprotein (LDL) receptor gene suggest that most, if not all, of relatively severe hereditary hypercholesterolemia associated with Achilles tendon xanthomas is caused by a defect of the LDL receptor gene, and that the origin of the mutant LDL receptor gene generally differs among different pedigrees in the Japanese population. On the other hand, data obtained by population and family studies suggest that hereditary moderate hypercholesterolemia due to abnormal gene(s) distinct from the abnormal LDL receptor gene may be more common than classic FH. As to the apolipoprotein A-I (apoA-I) gene, a mutant apoA-I gene with a codon 84 nonsense mutation which caused apoA-I deficiency, a marked reduction of HDL cholesterol and premature CHD is described. This finding suggests that a mutant apoA-I gene can act as a major gene for decreased levels of apoA-I and HDL cholesterol. Finally, application of genetic data for the prevention of premature CHD are discussed.

To investigate the association of apolipoprotein (APO) E4 and hypercholesterolemia in children, we studied the APOE phenotypes of 51 school-age children with hypercholesterolemia and of 51 age, sex and obesity index-matched controls with normocholesterolemia by two-dimensional gel electrophoresis APOE4 was present in 21 of 51 hypercholesterolemic children (41.2%), and in nine of 51 control subjects (17.6%). The difference was significant (p less than 0.01). This finding indicates that APOE4 is associated with hypercholesterolemia in children.

A 2-year-old boy, whose clinical abnormalities included growth retardation(3rd percentile), mild mental retardation (DQ = 67), microcephaly, hypertelorism, strabismus, prominent nasal bridge, stubby nose, pointed chin, undescended testes and hydronephrosis, had a ring chromosome 10. Using high-resolution banding technique, the breakpoints were decided at p15.3 and q26.3 of chromosome 10. The clinical features observed in this case were common in 8 other cases with ring chromosome 10 previously reported. Thus, the terminal deletion of both arms of chromosome 10 seems to be the cause of the specific clinical abnormalities. When a patient has the clinical common abnormalities above mentioned, ring chromosome 10 syndrome will be suspected before chromosome analysis.