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1.
Summary Two boys (W. M. and C. P.) are described, in each of whom a short-arm deleted C chromosome was apparently present. The clinical findings on W. M. are stenosis of the sagittal sutura associated with atrophy of the nervus opticus and mental retardation, and on C. P. osteogenesis imperfecta. An analysis of the G- and Q-banding patterns revealed in each patient a 12p—chromosome. The deletion involved most of band p12 as shown by length measurements on G-banded chromosomes. Both cases were compared to proven and presumed cases of 12p—from literature, but no common clinical phenotype could be demonstrated.  相似文献   

2.
Selection for nursing ability and adult weight in mice   总被引:1,自引:0,他引:1       下载免费PDF全文
Three selection treatments were conducted for 12 generations in each of two base populations (P and Q): (1) increased nursing ability of the mother (n12), as measured by mean 12-day weight of eight young within a crossfostering set (M(P) and M(Q) lines), (2) increased adult (42-day) body weight of the offspring (w42) (W(P) and W( Q) lines), and (3) performance combining the two traits (n12 and w42) into a selection index (B(P) and B(Q) lines). Lines C( P) and C(Q) were maintained as unselected controls in each population. In each line-generation subclass, 92 single-pair matings were made and the offspring assigned to balanced crossfostering sets of four dams each. Regression coefficients of mean performance (in grams) on generations were 0.080 +/-0.029 and 0.054 +/- 0.031 for n12 in M(P) and M(Q), and 0.680 +/- 0.039 and 0.868 +/- 0.051 for w42 in W(P) and W(Q), respectively. The B(P) and B(Q) lines showed genetic gains in n12 (0.090 and 0.053, respectively) and w42 (0.576 and 0.696) intermediate between the performance of M(P) and W(P), and M(Q) and W(Q), respectively, except for n12 of B(Q). Realized heritabilities for n12 were 0.16 +/- 0.05 and 0.11 +/- 0.06 and those for w42 were 0.40 +/- 0.02 and 0.43 +/- 0.03 for P and Q, respectively. The realized genetic correlations between n12 and w42 were 0.70 +/- 0.07 and 0.73 +/- 0.08 in P and Q, respectively. The ratios of the predicted to observed responses in M(P), B(P) and B(Q) were 0.99, 1.03 and 0.89, respectively. However, the predicted and observed responses differed in M( Q), W(P) and W(Q); the ratios were 1.29, 0.65 and 0.65, respectively. The observed combined responses for n12 and w42 in the index lines (B(P) and B(Q)) were smaller than the optimum expected from index selection. A possible cause was that the estimated genetic correlations (0.22 +/- 0.16 and -0.17 +/- 0.16 for B(P) and B( Q), respectively) and heritabilities (0.39 +/- 0.03 and 0.28 +/- 0.02, respectively) for w42 that were used to construct the selection index were smaller than the respective realized parameters.  相似文献   

3.
Microtubule (MT) dynamics and organization change markedly during interphase-M phase transition of the cell cycle. This mini review focuses first on p220, a ubiquitous MT-associated protein of Xenopus. p220 is phosphorylated by p34cdc2 kinase and MAP kinase in M phase, and concomitantly loses its MT-binding and MT-stabilizing activities. A cDNA encoding p220 was cloned, which identified p220 as a Xenopus homolog of MAP4, and p220 was therefore termed XMAP4. To examine the physiological relevance of XMAP4 phosphorylation during mitosis, Xenopus A6 cells were transfected with cDNA encoding wild-type or various XMAP4 mutants fused with a green fluorescent protein (GFP). Mutations of serine and threonine within potential phosphorylation sites for p34cdc2 kinase to nonphosphorylatable alanine interfered with mitosis-associated reduction in MT-affinity of XMAP4 and their overexpression affected chromosome movement during anaphase A. These results indicated that phosphorylation of XMAP4 by p34cdc2 kinase is responsible for the decrease in its MT-binding and MT-stabilizing activities during mitosis which are important for chromosome movement during anaphase A. The second focus is on a novel monoclonal antibody W8C3, which recognizes alpha-tubulin. W8C3 stained spindle MTs but not interphase MTs of Xenopus A6 cells, although tubulin dimers in M phase and interphase were equally recognized by this antibody. The difference in MT staining pattern may be because the W8C3-recognition site on alpha-tubulin is sterically hidden in interphase MTs but not in spindle MTs.  相似文献   

4.
三种龟类动物的细胞遗传研究   总被引:2,自引:0,他引:2  
本文以外周血淋巴细胞为材料,首次报道马来闭壳龟和地龟的核型,G带,C带和Ag-NORs,以及平胸龟的G带和C带,发现平胸龟的核型与前人报道的有差异。研究结果表明:平胸龟2n=54(14M+4ST+8T+28m),N.F.=72,7+6+14。A组No.6q per有一次缢痕。Ag-NORs位于A组的No.7 q ter。其全部染色体的着丝粒区均显示阳性C带,并且A组的No.7整条异染色质化;马来闭  相似文献   

5.
在猪12号染色体上定位数量性状位点   总被引:3,自引:0,他引:3  
为了找出猪12号染色体上的数量性状位点,在2个家系中测定了10个遗传标记,并记录了51个重要经济性状。该2家系,一个由欧洲野猪与皮特兰杂交而成,另一个由梅山与皮特兰杂交建成。应用最小二乘法进行了数量性状位点定位,同时进行了生长激素基因型与性状间的相关分析。应用最小二乘法并未发现数量性状位点,而应用相关分析发现生长激素基因型与某些膘情性状高度相关。带有基因型C1A2/C4A2的猪比带有基因型C2A2  相似文献   

6.
T R Sukhikh 《Tsitologiia》1992,34(2):72-76
A chimpanzee family was studied, in which the father had a balanced translocation t(17p--; 23p+). The mother showed the normal female chromosome complement. Their daughter had also the normal female karyotype, but with heteromorphic chromosomes 23. A cytogenetic analysis was made using G- and Q-banding techniques and in addition an alkaline silver method for NOR staining. A mechanism of the translocation inheritance is discussed.  相似文献   

7.
Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is the most frequent inborn error of metabolism, and accounts for 90-95% of CAH cases. The affected enzyme, P450C21, is encoded by the CYP21A2 gene, located together with a 98% nucleotide sequence identity CYP21A1P pseudogene, on chromosome 6p21.3. Even though most patients carry CYP21A1P-derived mutations, an increasing number of novel and rare mutations in disease causing alleles were found in the last years. In the present work, we describe five CYP21A2 novel mutations, p.R132C, p.149C, p.M283V, p.E431K and a frameshift g.2511_2512delGG, in four non-classical and one salt wasting patients from Argentina. All novel point mutations are located in CYP21 protein residues that are conserved throughout mammalian species, and none of them were found in control individuals. The putative pathogenic mechanisms of the novel variants were analyzed in silico. A three-dimensional CYP21 structure was generated by homology modeling and the protein design algorithm FoldX was used to calculate changes in stability of CYP21A2 protein. Our analysis revealed changes in protein stability or in the surface charge of the mutant enzymes, which could be related to the clinical manifestation found in patients.  相似文献   

8.
This paper deals with the chromosome morphology of three wild eggplants (Solanum indicum L., S. indicum L. var. recurvatum C. Y. Wu et S. C. Huang,S. coagulans Forsk.) grown in Shi-shuang-banna and two cultivars (S. melongena L.var. serpentinum Bailey, S. melogena L. var. esculantum Nees). All their chromosomenumbers are 2n=24. The chromosome idiograms of wild eggplants axe as follows: Solanum indicum,2G+12J+2I+8M; S. indicum var. recurvatum, 8G+12J+2I+2M; S. coagulans ( No. 20),10J+2I+12M; S. coagulans(No. 21), 8J+14M+2L; and those of cultivars are: S. melongena var. serpentinum, 6G+12J+2I+4M; S. melongena var. esculantum, 12J+2I+10M. The chromosome idiograms among three wild eggplants are quite different. However, they are rather closely related in each other between the two cultivars. Butthe relative length and the relative position of the sat-chromosomes in each chromo)meidiogram are conspicuously variable.  相似文献   

9.
Evidence is presented from C-banding studies that the W chromosome of eleven species of snakes is not homogeneous in nature but is differentiated linearly into alternating lighter and darker C positive regions. The same is true of the W chromosome of at least some birds. There is evidence from the literature indicating a similar differentiation of the Y chromosome of some mammals and here the intermediate C positive regions are deficient in highly repetitive DNA. The significance of heterochromatinization as a means of generating differentiated sex chromosomes is discussed in the light of these findings.Dedicated to Professor M.J.D. White on the occasion of his 70th Birthday  相似文献   

10.
Abnormalities of some oncogenes, antioncogenes and losses of heterozygosity (LOH) of chromosome 11p, 17p, and 17q in colorectal carcinomas (CC) was studied. Amplification of ERBB-1/HER-1 oncogene was detected in 2 of 56 cases; ERBB-2/HER-2- in 4 of 62. There was a lack of evidence for C-MYC oncogene amplification (67 cases). LOH of chromosome 11p (HRAS-1 probe) was found in 2 of 37 informative (heterozygous) cases; such events were not accompanied by point mutations in "hot" codons (12th or 61st) in the remaining allele. Prevalence of A3 and A4 alleles of HRAS-1 oncogene (68 cases) as compared to healthy donors was noted. RB-1 (41 cases) and p53 (62 cases) suppressor genes did not show any alterations in Southern-blot analysis. LOH of chromosome 17p (YNZ-22 probe) was found in 15 of 26 heterozygous CC; 17q (THH-59 probe)--in 4 of 16. Analysis of 175th codon of p53 gene revealed only one case of mutation in 35 CC studied. Finally, we were able to detect genetic alterations in 23 of 40 (58%) CC, that were studied on each parameter using Southern-blot. We failed to find any correlation between various molecular abnormalities or clinical characteristics. The data obtained are in disagreement with the view concerning frequent involvement of p53 antioncogene in chromosome 17p deletions.  相似文献   

11.
We identified phage clones containing insertion element IS5 in a set of 476 lambda phage clones carrying chromosomal segments that cover almost the entire chromosome of Escherichia coli K-12 W3110. Precise locations and orientations of IS5 were then determined by cleavage analysis of phage DNAs containing them. We mapped 23 copies of IS5 (named is5A to is5W) on the W3110 chromosome. Among them, ten were identified as the common elements present at the same locations in both chromosomes of W3110 and another E. coli K-12 strain, JE5519. While most of the mapped IS5 elements were scattered over the W3110 chromosome, four copies of IS5 (designated is5L, is5M, is5N and is5O) were in a region representing tandem duplication of a DNA segment flanked by two copies of IS5. Interestingly, one unit of this DNA segment as well as a portion of it was seen also in a tandem array in a different region where two copies of IS5 (designated is5P and is5Q) were present. In particular two pairs of the mapped IS5 elements may have been involved in inversion of the chromosomal segments in two of the E. coli K-12 derivatives.  相似文献   

12.
广义烙铁头属三种烙铁头的核型及分类地位初步探讨   总被引:2,自引:0,他引:2  
报道3种烙铁头蛇的核型。其中,烙铁头2n=36=16M(14V+2SV/V)+20m,ZW型性决定,Z为V型,W为SI/SV型,Z明显大于W;菜花烙铁头2居群2n=36=16M(14V+2SI)+20m,ZW型性决定,Z为V型,W为SI型,Z明显大于W;云南竹叶青2n=36=16M(12V/SV+2SV/SI+2SI)+2m,无异型性染本,对3种的核型及烙铁头属已知核型进行了比较分析,并对云南竹叶  相似文献   

13.
The W chromosome of the silkworm Bombyx mori is devoid of functional genes, except for the putative female-determining gene (Fem). To localize Fem, we investigated the presence of W-specific DNA markers on strains in which an autosomal fragment containing dominant marker genes was attached to the W chromosome. We produced new W-chromosomal fragments from the existing Zebra-W strain (T(W;3)Ze chromosome) by X-irradiation, and then carried out deletion mapping of these and sex-limited yellow cocoon strains (T(W;2)Y-Chu, -Abe and -Ban types) from different Japanese stock centers. Of 12 RAPD markers identified in the normal W chromosomes of most silkworm strains in Japan, the newly irradiated W(B-YL-YS)Ze chromosome contained three, the T(W;2)Y-Chu chromosome contained six, and the T(W;2)Y-Abe and -Ban chromosomes contained only one (W-Rikishi). To investigate the ability of the reduced W-chromosome translocation fragments to form heterochromatin bodies, which are found in nuclei of normal adult female sucking stomachs, we examined cells of the normal type p50 strain and the T(W;2)Y-Chu and -Abe strains. A single sex heterochromatin body was found in nuclei of p50 females, whereas we detected only small sex heterochromatin bodies in the T(W;2)Y-Chu strain and no sex heterochromatin body in the T(W;2)Y-Abe strain. Since adult females of all strains were normal and fertile, we conclude that only extremely limited region, containing the W-Rikishi RAPD sequence of the W chromosome, is required to determine femaleness. Based on a comparison of the normal W-chromosome and 7 translocation and W-deletion strains we present a map of Fem relative to the 12 W-specific RAPD markers.  相似文献   

14.
The region between residues 968 and 1882 of apolipoprotein B (apoB-21 to apoB-41) is rich in amphipathic beta strands (AbetaSs) and promotes the assembly of primordial triacylglyceride (TAG)-rich lipoproteins. To understand the importance of AbetaS in recruiting TAG, the interfacial properties of two AbetaS consensus peptides, P12 and P27, were studied at dodecane/water (DD/W) and triolein/water (TO/W) interfaces. P12 (acetyl-LSLSLNADLRLK-amide) and P27 (acetyl-LSLSLNADLRLKNGNLSLSLNADLRLK-amide), when added into the aqueous phase surrounding a suspended oil drop (dodecane or triolein), decreased the interfacial tension (gamma) in a concentration-dependent manner. At the DD/W interface, 1 x 10(-5) M P12 decreased gamma to approximately 20 mN/m and 6.6 x 10(-6) M P27 decreased gamma to approximately 13 mN/m. At the TO/W interface, 1.5 x 10(-5) M P12 decreased gamma to approximately 14 mN/m and 9.0 x 10(-6) M P27 decreased gamma to approximately 12 mN/m. The surface area of both peptides was between 11.2 and 15.1 angstroms2 per residue, consistent with beta sheets lying flat on DD/W and TO/W interfaces. P12 and P27 are almost purely elastic on DD/W, TO/W, and air/water interfaces. When P12 and P27 were compressed beyond the equilibrium gamma to as low as 4 mN/m, they could not be readily desorbed from either interface. These properties probably help in assembling nascent TAG-rich lipoproteins, and AbetaS may anchor apoB to beta lipoproteins.  相似文献   

15.
Gaucher disease (GD) is the most frequent lysosomal storage disease presenting in all populations. Mutations in the acid β-D-glucosidase gene (GBA) cause development of GD, resulting in a decrease or full loss of activity of this enzyme. We report here the results of the molecular-genetic analysis in 68 Russian GD patients from 65 families with the three types of this disease. The GD genotype has been completely elucidated in 58 patients and in all patients we have found at least one mutant allele (92.6%). Besides frequent mutations (p.N370S, c.1263_1317del (del55), p.L444P, p.R463C, Rec NciI) we have identified rare mutations p.R120W, p.R170C, p.R184W, p.G202R, Rec C (p.R120W; p.W184R; p.N188K; p.V191G; p.S196P; p.G202R; p.F213I), presenting in other populations of GD patients. The mutations p.P236T, p.L249Q, p.L288P, p.P319S, p.V352M, p.W381X, p.A384D identified in this study had not been described before. The GBA mutations identified in Russian patients have been compared with those found in patients of other European countries. Genotype-phenotype correlations in GD are discussed.  相似文献   

16.
云南无量山四种报春花属植物的核型研究   总被引:6,自引:0,他引:6  
研究了云南无量山报春花属(Primula)3组4种植物的核型。体细胞中期染色体的数目和核型分别为:波缘报春P.sinuata Franch,2n=2x=22-20m(2SAT)_ 2st,着丝点端化值(T.C.%)为57.51%;无葶脆蒴报春P.sinoexscapa C.M.Hu,2n=2x=22=20m 2sm,T.C.%值为57.78%;滇北球花报春P.denticulata ssp.sinodenticulata (Balf.F.et Forrest)W.W.Smith,2n=2x=22=20m(4SAT) 2st,T.C.%值为56.79%;光叶景东报春P.interjacens var.epilosa C.M.Hu,2n=2x=18=2m(2SAT) 6sm(4SAT) 10st,T.C.%值为67.47%。简要讨论了报春花属植物可能的染色体原始基数和3个组的染色体基数。  相似文献   

17.
It is necessary to consider breed and cold tolerance in the housing and caring of horses. This study demonstrates differences in heat loss between horse types at low temperatures and examines rate of loss in different types during different seasons. Eighteen horses participated. Groups by type were light (L), warmblood (W), coldblood (C), and pony (P). A camera filmed thermographic images at 15 degrees C, 2 degrees C (all types), -8 degrees C (L, W, C), and -12 degrees C (P). The study calculated loss from the neck, trunk, and inner surfaces of front and hind legs. Loss was similar in all types at 15 degrees C. L, W, and C dissipated more heat at 2 degrees C than at 15 degrees C (p < .001) and from neck and trunk at -8 degrees C than at 2 degrees C (p < .05). P dissipated heat similarly at 2 degrees C and -12 degrees C. At 2 degrees C, loss was less from neck and trunk in C and P compared with L (p < .05). At -8 degrees C, loss in L and W was greater than in C (p < .05).  相似文献   

18.
Inheritance of chromosomes 3 and 11 in the families with Chuvash autosomal recessive polycythemia and in control group with no disease symptoms was examined using polymorphic dinucleotide markers D3S1597 and D3S1263, mapped to region 3p25, and D11S4111, D11S4127, and D11S1356, mapped to region 11q23. All patients were homozygous for the C598T mutation in the VHL gene (3p25). The analysis showed that in 75% of the cases, chromosome 3 carrying C598T mutation was coinherited with certain chromosome 11, which differed from 50%, expected upon independent inheritance of each chromosome. In case of chromosome 3 without C598T mutation, this pattern was observed neither in healthy sibs form the families with autosomal recessive polycythemia (44%), nor in the control group (43%). These results suggest that in case of the C598T mutation in the VHL gene, chromosomal loci 3p25 and 11q23 are inherited not independently, compared to the inheritance of these loci in the absence of the mutation in healthy sibs from the affected families (chi2 = 16.14; P < 0.001), and also in the control family sample (chi2 = 17.91; P < 0.001).  相似文献   

19.
20.
Summary Two cases of trisomy 12p due to a familial translocation t(12;21) (p11;p11) inherited through three generations are presented. The clinical features of both affected individuals are consistent with those previously reported. Study of the NORs by silver staining showed translocation of the NOR from chromosome 21 onto the der(12) and suggested that the activity of this site has been suppressed in some carriers.  相似文献   

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