Authors: L.K. Pandey, S. Pandey, J. Gupta and A.K. Saxena
Infertility is a major reproductive health threat; the frequency of male infertility due to Y-chromosome microdeletions is 13-18% in the human population; these microdeletions involve recurrent loss of three non-overlapping regions designated as AZFa, AZFb and AZFc, associated with spermatogenic failure. Several contradictory .. Read More»
Authors: Q. Xie, H. Kang, D.L. Sparkes, S. Tao, X.M. Fan, L. Xu, X. Fan, L. Sha, H. Zhang, Y. Wang, J. Zeng and Y. Zhou
The dynamics of rye chromosomes during mitosis and meiosis was analyzed in a subset comprising 33 F3 lines from the cross of wheat, Psathyrostachys huashanica amphiploid (AABBDDNsNs) and hexaploid triticale (AABBRR), as visualized by genomic in situ hybridization. The results indicated that 31 of the total lines contained 4-14 rye chromosomes. Twenty-eigh.. Read More»
Authors: M.D.A. Nery, M.A.O. Alves, H.D. Aquino, E.A. Nery, L.B.M. Bezerra, R.T.M. Ribeiro and H.S.A. Monteiro
Cytogenetic studies of Philodryas nattereri and Philodryas olfersii revealed a diploid chromosome number 2n = 36 for both species (3 metacentrics, 4 submetacentrics, and 10 acrocentrics, with a fundamental number of 51 and 52, respectively). The results obtained are novel and similar to those previously described for species belonging to the Dipsadidae fa.. Read More»
Authors: C.P. Sodr�?©, R.S. Guilherme, V.F.A. Meloni, D. Brunoni, Y. Juliano, J.A.D. Andrade, S.I.N. Belangero, D.M. Christofolini, L.D. Kulikowski and M.I. Melaragno
Ring chromosomes are often associated with abnormal phenotypes due to loss of genomic material and also because of ring instability at mitosis after sister chromatid exchange events. We investigated ring chromosome instability in six patients with ring chromosomes 4, 14, 15, and 18 by examining 48- and 72-h lymphocyte cultures.. Read More»
Authors: C.O.A. Melo, A.R. Danin, D.M. Silva, J.A. Tacon, K.K.V.O. Moura, E.O.A. Costa and A.D. da Cruz
The androgen receptor is encoded by a single-copy gene located in the long arm of the X chromosome (Xq11-12); it consists of eight exons and encodes an intracellular transcription factor that belongs to the steroid/nuclear receptor superfamily. Disturbances in the function of the androgen receptor can lead to several forms of .. Read More»
Authors: H.L. Wang, B. Wu, K.M. Guo and R.H. Tian
Infertility as a psychological problem has gained increasing attention. Male partners among infertile couples have elevated levels of psychological distress, which could affect semen quality, result in hormonal abnormalities, and increase the occurrence of early miscarriage. Infertile women are more vulnerable to psychological.. Read More»
Authors: C. Garcia, C. Oliveira and L.F. Almeida-Toledo
Among catfish species of the genus Rhamdia reported for the Brazilian territory, R. quelen is the most widespread, being found in nearly all hydrographic basins of Brazil. Nowadays, R. quelen is a synonym for at least 47 other species in this genus, its taxonomic status still being controversial. The available cytogenetic repo.. Read More»
Authors: P.P. Mendon�?§a
Triatomines are hematophagous insects of great concern in public health because they are vectors of Trypanosoma cruzi, a protozoan that causes Chagas disease. Triatomines are also of great genetic interest, because they possess holocentric chromosomes and undergo an unusual form of meiosis with post-reductional segregation of .. Read More»
Authors: S. Ser�?§e, E. Ekbi�?§, J. Suda, K. G�?¼nd�?¼z and Y. Kiyga
Myrtle is an evergreen shrub or small tree widespread throughout the Mediterranean region. In Turkey, both cultivated and wild forms, differing in plant and fruit size and fruit composition, can be found. These differences may have resulted from the domestication of the cultivated form over a long period of time. We investigat.. Read More»
Authors: D.E.S. Leme, D.H. Souza, G. Mercado, E. Pastene, A. Dias and D. Moretti-Ferreira
Williams-Beuren syndrome (WBS) is a genetic disorder characterized by physical and intellectual developmental delay, associated with congenital heart disease and facial dysmorphism. WBS is caused by a microdeletion on chromosome 7 (7q11.23), which encompasses the elastin (ELN) gene and about 27 other genes. The gold standard for WBS laboratory diagnosis i.. Read More»