Erythrocyte alloantigen loci Ea-D and Ea-I map to chromosome 1 in the chicken

A test cross was conducted to analyse some linkage relationships in the chicken. Pea comb (P), naked neck (Na), tardy feathering (t), four erythrocyte alloantigen loci (Ea-C, -D, -I, -P), and the rearrangement break point (RB) of the NM 7092 t(Z;1) chromosome translocation were tested. Significant linkages were found between P and Ea-I (32.9 +/- 4.2), the RB and Ea-D (30.7 +/- 4.3), and t and Ea-D (38 +/- 4.8). The data suggest the linear order of t, Ea-D, and the RB, with t closest to the centromere. Significant linkage was also found between Na and Ea-P (32.4 +/- 4.9), confirming earlier reports.     

18-26S rDNA在4种重楼属植物中的定位

为探讨rDNA在重楼属Paris L.中的分布规律,利用荧光原位杂交（FISH）对4种重楼属植物 的18-26S rDNA进行了定位。所有植物均为二倍体,基因组由A、B、C、D和 E5条染色体构成。（1）滇重楼P.polyphylla var.yunnanensis:2n=10=6m+4t,C和D染色体的 短臂上各有1个18-26S rDNA位点;（2）长柱重楼P.forrestii:2n=10=6m+4t,B染色体的长臂 、C和D染色体的短臂上各有1个位点;（3）五指莲P.axialis:2n=10=6m（2sat）+4t（2sat） +1-2B,C和D染色体的短臂上各有1个位点;在有1个B染色体的细胞中,B染色体没有信号点, 而有2个B染色体的细胞中,只有1个B染色体上有信号点,表明B染色体上有基因存在且其分裂 不均等;（4）大理重楼P.daliensis:2n=10=4m+2sm+2st+2t,C染色体的短臂上有1个位点。1 8-26S rDNA位点不仅出现在染色体的次缢痕上,也出现在非次缢痕位点。另外,4个种中C染 色体短臂末端均有18-26S rDNA。     

New chromosomal translocations correlate with specific immunophenotypes of childhood acute lymphoblastic leukemia

Cytogenetic analysis of leukemic cells obtained at diagnosis from 122 patients with childhood acute lymphoblastic leukemia (ALL) disclosed chromosomal translocations in 36 cases. Two new nonrandom translocations were identified and found to be associated with specific immunophenotypes of the disease. The first, identified in 4 of 16 cases of T-cell ALL positive for sheep erythrocyte receptors (E+), involved the short arm (p) of chromosome 11 and the long arm (q) of chromosome 14 and was designated t(11;14) (p13;q13). The second, found in 7 of 23 cases with a pre-B-cell phenotype, involved the long arm of chromosome 1 and the short arm of chromosome 19; it was designated t(1;19) (q23;p13.3). A third abnormality involving a common breakpoint on chromosome 12 (band p 12) was also identified. These two new differentiation-specific translocations suggest a mechanism for aberrant expression of genes that influence lymphoid cell growth and development, as well as leukemogenesis.     

Mapping of18-26S rDNA loci in four species of the genus Paris by fluorescence in situ hybridization（FISH）

18-26S rDNA loci were mapped on chromosomes in four species of Par is,and the num-ber and position of rDNA sites in these species were compared f or analysis of the distribution of the sites. All the plants were diploids,and t he genome consisted of five chromosomes,A,B,C,D and E. （1）P. polyphylla var. yunnanensis,2n=10=6m+4t. Two18-26S rDNA loci were de-tected on the short arms o f C and D chromosomes;（2）P. forrestii,2n=10=6m+4t. One locus was detected on th e long arm of B chromosome,and also two loci on the short arms of C and D chromosomes;（3）P. axialis. 2n=10=6m（2sat）+4t（2sat）+1-2B. Two loci were detected o n the short arms of C and D chromosomes. One locus was detected in the cell with t wo B-chromosomes（B）,but none was detected in that with only one B chromosome, indicating that rRNA gene existed on B chromsome,and an unequal division occurr ed during mitotic cycle of B-chromosomes. （4）P. daliensis,2n=10=4m+2sm+2st+2t. O ne locus was detected on the short arm of D chromo-some. The signals of18-26S rD NA appeared not only in the second constriction but also in the other regions of chromosome. It is noteworthy that one locus was detected in the terminal region o n the short arm of C chromosome in all the four species studied.     

Reciprocal translocation between Y chromosome long arm euchromatin and the short arm of chromosome 1

A case with an apparently balanced reciprocal translocation between the long arm of the Y chromosome and the short arm of chromosome 1 t(Y;1)(q11.2;p34.3) is described. The translocation was found in a phenotypically normal male ascertained by infertility and presenting for intra-cytoplasmatic sperm injection treatment. Histological examination of testicular biopsies revealed spermatogenic failure. Chromosome painting with probes for chromosome 1 and for the euchromatic part of the Y chromsome confirmed the translocation of euchromatic Y chromosomal material onto the short arm of chromosome 1 and of a substantial part of the short arm of chromosome 1 onto the Y chromosome. Among the Y/autosome translocations, the rearrangements involving long arm euchromatin of the Y chromosome are relatively rare and mostly associated with infertility. Microdeletion screening at the azoospermia locus revealed no deletions, suggesting another mechanism causing infertility in this translocation carrier.     

Study of androgenetic performance and molecular characterisation of a set of wheat-rye addition lines

Rye chromosomes of wheat-rye addition lines were successfully identified by means of an RFLP analysis with 30 probes. Our results are in agreement with previous cytological data concerning the identity of lines F (+1R), D (+2R), C (+3R), A (+4R), E (+5R) and B (+7R). Two categories of chromosomal rearrangements have been distinguished, namely: (1) deletions: the current line D possesses a chromosome 2R deleted on its short arm and the line G a chromosome 3R deleted on its long arm; we have also noticed a deletion on the long arm of wheat chromosome 1A in line F61; and (2) evolutionary reciprocal translocations in rye relative to wheat which have been previously mentioned in the literature. The anther culture response of the different lines was studied. A significant difference between FEC 28 and the addition lines was observed for embryo production and plant regeneration. It appears that genes located on S 10 chromosome arm 3RL and on FEC 28 chromosome arm 1AL increase embryo frequency whereas gene(s) located on S 10 chromosome 5R reduce(s) it. Plant regeneration results suggest that genes increasing regeneration ability and green-plant frequency are located on S 10 chromosome 4R. The long arm of chromosome 1A seems to be involved positively in green-plant regeneration whereas chromosomes 1R and 3R limit plant regeneration.     

Alloplasmic wheat - Elymus ciliaris chromosome addition lines.

Alloplasmic euploid wheat with the cytoplasm of Elymus ciliaris (2n = 4x = 28, ScScYcYc) is male sterile and has reduced vigor. However, alloplasmic plants with E. ciliaris chromosomes 1Sc or 1Yc marked by gliadin genes Gli-Sc1 and Gli-Ycl, respectively, are vigorous and fertile. The Rf genes on 1Sc and 1Yc are named Rf-Sc1 and Rf-Yc1. Two chromosome translocations involving 1Yc were isolated. The first involved the short arm of 1Yc translocated to the short arm of wheat chromosome 3B. The second involved the short arm of 1Yc translocated to the short arm of a chromosome, designated L, of E. ciliaris. The second line also has another E. ciliaris chromosome designated A and lacks wheat chromosome 6A. This line is resistant to Puccinia recondita. The relationship between fertility restoration and nucleolar organizing regions is discussed. Key words : Triticum aestivum, Elymus ciliaris, chromosome addition, Rf genes, nucleolar organizing regions.     

Partial trisomy of chromosome no. 1 in two adult brothers due to maternal translocation (1q-;6p+)

Summary Extra chromosome material on the short arm of chromosome no. 6 (46,XY,6p+) was found in two mentally retarded adult half-brothers with mildly dysmorphic features. The phenotypically normal mother had a balanced translocation between the long arm of chromosome no. 1 and the short arm of chromosome no. 6: 46,XX,t(1;6)(q32;p25). Thus the two affected brothers were trisomic for the long arm segment of chromosome no. 1, distal to q32. These patients, with mildly dysmorphic features and mental retardation, represent the first cases of partial trisomy 1q surviving to adulthood.The clinical and cytogenetic data obtained from eight individuals with partial trisomies for different long arm segments of chromosome no. 1 suggest that partial trisomy of the distal two-thirds of the long arm is characterized by severe malformations, growth retardation, and early death. Conversely, partial trisomy for the distal one-third of the long arm is associated with milder malformations and longer survival time as well as growth and mental retardation.     

A, 1;6, translocation associated with congenital glaucoma and cleft lip and palate.

A translocation of a part of the long arm of a chromosome No. 1 onto the long arm of a chromosome No. 6 was observed in a 2 1/2-year-old boy with mental retardation, harelip, cleft palate and congenital glaucoma. Different banding methods revealed that the translocation t(1;6)(q23;q27) apparently was balanced. The conncection between the patients' symptoms and the chromosomal rearrangement might be fortuitous or produced by the chromosome aberration.     

Meiotic behaviour of single-arm tetrasomic combinations of isochromosomes,telocentrics and normal chromosomes in rye (Secale cereale L.)

The isochromosome studied was derived from the short arm of the satellite chromosome of rye (Secale cereale, 2n=14); the telocentrics represent both the short and long arms of the same chromosome. Three different combinations, tetrasomic for the short arm, have been composed and studied: I: 2 isochromosomes (short arm) + 2 telocentrics (long arm) + 6 normal pairs. II: 1 isochromosome + 2 telocentrics (short arm) + 2 telocentrics (long arm) + 6 normal pairs. III: 1 isochromosome + 1 telocentric (short arm) + 1 normal satellite chromosome + 1 telocentric (long arm) + 6 normal pairs. — Over 20,000 cells were analysed. Simple mathematical models describing the frequencies of the different types of MI configurations in terms of frequency of chiasmata in the different pairing combinations of the polysomic arms, and of the frequency of multivalent pairing of this arm, were developed. They were used to derive estimates for chiasma frequencies and multivalent pairing frequencies in the different chromosome constitutions from the observations on configuration frequencies. Variation between plants and within plants was studied, and it was concluded that much of the within plant heterogeneity was due to regulatory variation expressed independently in different chromosomal segments. There was also a significant genetic component. Analysis of the reasons for the models to fail under certain conditions led to suggestions for extension of the models.     

Human homologs of two testes-expressed loci on mouse chromosome 17 map to opposite arms of chromosome 6

Our laboratory has recently cloned and characterized two testes-expressed loci--the Tcp-10 gene family cluster and the D17Si11 gene--that map to the proximal portion of mouse chromosome 17. Human homologs of both loci have been identified and cloned. Somatic cell hybrid lines have been used to map the human homolog of D17Si11 to the short arm of chromosome 6 (p11-p21.1) along with homologs of other genes from the (Pim-1)-(Pgk-2) region of the mouse chromosome. The human TCP 10 locus maps to the long arm of chromosome 6 (q21-qter) along with homologs of other genes from the mouse chromosome 17 region between the centromere and Pim-1. The mapping of large portions of the mouse t haplotype to unlinked regions on human chromosome 6 rules out the possibility that a t-haplotype-like chromosome could exist in humans.     

Fusion of 9 beta-satellite and telomere (TTAGGG)n sequences results in a jumping translocation

A newborn was found to have an isochromosome for the short arm of chromosome 9, i(9p) and a jumping translocation of the whole long arm. In 94.4% metaphases, 9q was fused to the telomere of chromosome 19p and, in 5.6% of metaphases, 9q was fused to the telomere of chromosome 8p. The net result was trisomy for the short arm of chromosome 9. With the pan telomere probe, fluorescent in situ hybridization (FISH) investigations found an interstitial telomere on the der(19) and der(8). The 9 beta and classical satellite probes gave a signal only on the long arm of chromosome 9 involved in the jumping translocation. The 9 alpha satellite probe hybridized to i(9p) and not to the other derivative chromosomes. A combination of chromosome 9 (red) and chromosome 19 (green) paint probes used to rapidly screen metaphases for the jumping translocation found 88 metaphases had a der(19)t(9;19) and 4metaphases had a der(8)t(8;9). For the first time, the junction of a jumping translocation has been shown to involve the telomere sequence (TTAGGG)n and beta-satellite sequences by FISH. In this paper, we also review the simultaneous occurrence of an isochromosome for the short arm and translocation of the whole long arm and constitutional jumping translocations.     

A sequence-ready contig map of the top arm of Arabidopsis thaliana chromosome 3.

A fine physical map of the top arm of Arabidopsis thaliana chromosome 3 has been constructed by ordering P1, TAC and BAC clones using the sequences of a variety of DNA markers and end-sequences of clones. The marker sequences used in this study were derived from 58 DNA markers, 93 YAC end-sequences, and 807 end-sequences of P1, TAC and BAC clones. The entire top arm of chromosome 3, except for the centromeric and telomeric regions, was covered by a single contig 13.3 Mb long. This fine physical map will facilitate gene isolation by map-based cloning experiments as well as genome sequencing of the top arm of chromosome 3. The map and end-sequence information are available on the web site KAOS (Kazusa Arabidopsis data Opening Site) at [http://www.kazusa.or.jp/arabi/].     

Partial trisomy 13 as a result of de novo (6p;13q) translocation

Summary A newborn infant with the clinical features of the Patau syndrome was found to have excess chromosome 13 material present as a tandem translocation involving the short arm of chromosome 6 and the long arm of an extra chromosome 13: 46,XY,t(6;13)(p24;q12). The major part of the long arm of the extra chromosome 13 was attached linearly (tandem translocation) to the short arm of chromosome 6. Both parents were phenotypically and karyotypically normal.     

大鳞副泥鳅ZZ/ZW型性别决定的细胞遗传学证据

大鳞副泥鳅是鲤形目、鳅科的鱼类。其2n数为48,核型组成为12m+4sm+32 t(雄性),11m+5sm+32t(雌性)。根据银染带和C带特征分析,证实大鳞副泥鳅为ZZ/ZW型性别决定。Z染色体为中部着丝粒染色体,在其长臂端部有Ag -NOR存在。 W染色体为亚中部着丝粒染色体,在其长臂末端也有Ag-NOR存在,同时还有一深染的居间C带,这是W染色体独有的带纹特征。 Abstract:Paramisgurnus dabryanus belongs to Cypriniformes,Cobitidae.Its 2n is 48.The karyotype formula is 12m+4sm+32t(in male),11m+5sm+32t(in female).According to the Ag-NORs band and C-band patterns,we consider that its sex determination is of ZZ/ZW type.The Z chromosome is a metacentric one with Ag-NORs located on its arm end.The W chromosome is a submetacentric with Ag-NORs located on the terminal of its long arm.There is a darkly stained C-band on the long arm of W chromosome.This band is a characteric of the W chromosome.     

rDNA and acrocentric chromosomes in man

Summary A malformed female infant was found to have a 46,XX complement with a chromosome 8 shorter than normal with a secondary constriction and satellites on the short arm. Chromosome studies on the clinically normal father showed a balanced translocation between chromosome 8 and 13, i.e., 46,XY,t(8;13) (p21 p12). The proposita, carrier of the unbalanced form of the translocation, resulted partially monosomic for short arm of chromosome 8 (8p-) and partially trisomic for short arm of chromosome 13.The levels of DNA complementary to rRNA (normal in the father who had 10 NOR and increased in the proposita who had 11 NOR) confirmed our interpretation of the rearrangement.     

Familial Down syndrome due to t(10;21) translocation: evidence that the Down phenotype is related to trisomy of a specific segment of chromosome 21.

This report deals with a reciprocal t(10;21) translocation which is observed in three generations of a family. Included are examples of the balanced translocation, adjacent-2 segregation producing three patients with trisomy of the distal long arm of chromosome 21 and the Down syndrome, and 3-1 disjunction producing trisomy of the proximal segment of chromosome 21 in a mildly mentally retarded boy without phenotypic features of the Down syndrome. These data provide evidence that the Down phenotype is attributable to trisomy of the distal long arm of chromosome 21.     

Lack of tumor suppression but induced loss of copies of indigenous chromosome 10 in vitro following microcell-mediated transfer of a deleted human der(9)t(X;9) chromosome to Syrian hamster BHK-191-5C cells

We have previously shown that microcell-mediated transfer of a der(9)t(X;9) chromosome, containing an almost complete human chromosome (HSA) 9 derived from the human fibroblast strain GM0705, into the Syrian hamster (Mesocricetus auratus) cell line BHK-191-5C suppressed the anchorage independence and tumorigenicity of the hybrids. Transfer of a normal HSA X did not have any effect on these phenotypes. Although the recipient cell line contained a 1:1 ratio of near-diploid and near-tetraploid cells, all hybrids retaining the der(9) chromosome were near-tetraploid, in contrast to hybrids retaining a normal X chromosome. In the present study, we have generated microcell hybrids by transferring another der(9)t(X;9) chromosome derived from the human fibroblast strain GM01429. This derivative chromosome contained a deletion on the short arm of HSA 9 and was also missing the distal part of the long arm of HSA 9 due to the involvement in a reciprocal (constitutive) translocation of this chromosome with HSA X. Cytogenetic analysis showed that all hybrid clones were near-tetraploid, confirming our previous finding. We also observed that the introduction of the deleted der(9) chromosome forced the hybrids to lose Syrian hamster chromosome 10. A soft agar test and nude mice assay indicated that none of the hybrids was suppressed for either anchorage independent growth or tumor formation. These data suggest that there is an antagonistic relationship between growth-promoting genes and antiproliferative genes. The observed dosage effects of both growth-promoting and growth-suppressing genes indicate that cellular growth may be a quantitative trait.     

Requirement of the human chromosome 11 long arm for replication of herpes simplex virus type 1 in nonpermissive Chinese hamster x human diploid fibroblast hybrids

Somatic cell hybrids between Chinese hamster (CH) lung cells (V79/380-6), nonpermissive for productive infection by herpes simplex type 1 (HSV-1), and permissive human diploid cells support productive HSV-1 infection as long as they retain human chromosome 11. Human chromosome 3 has been reported to complement nonpermissivity in (CH) Don cells (1). Intraspecies hybrids between Don/a3 and V79/380-6 cells, however, did not support HSV-1 replication, indicating lack of complementation. The block in both nonpermissive CH cell lines was determined to involve a step beyond replication of the parental viral DNA. In cell hybrids between nonpermissive Don/a23 cells and human fibroblasts containing a t(11;15) (p11;p12) translocation, HSV-1 production was dependent solely on the presence of either human chromosome 11 or the der(11) (p11 leads to qter) translocation product containing the long arm of chromosome 11. Chromosome 3 was excluded by a discordancy rate of 59%. We conclude that the long arm of human chromosome 11 carries one or more genes coding for host functions necessary for the production of progeny HSV-1 DNA.