Chromosomes in a genome-wise order: evidence for metaphase architecture.
BACKGROUND
One fundamental finding of the last decade is that, besides the primary DNA sequence information there are several epigenetic "information-layers" like DNA-and histone modifications, chromatin packaging and, last but not least, the position of genes in the nucleus.


RESULTS
We postulate that the functional genomic architecture is not restricted to the interphase of the cell cycle but can also be observed in the metaphase stage, when chromosomes are most condensed and microscopically visible. If so, it offers the unique opportunity to directly analyze the functional aspects of genomic architecture in different cells, species and diseases. Another aspect not directly accessible by molecular techniques is the genome merged from two different haploid parental genomes represented by the homologous chromosome sets. Our results show that there is not only a well-known and defined nuclear architecture in interphase but also in metaphase leading to a bilateral organization of the two haploid sets of chromosomes. Moreover, evidence is provided for the parental origin of the haploid grouping.


CONCLUSIONS
From our findings we postulate an additional epigenetic information layer within the genome including the organization of homologous chromosomes and their parental origin which may now substantially change the landscape of genetics.
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany.
Anja
A
Weise
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany.
Samarth
S
Bhatt
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany.
Katja
K
Piaszinski
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany.
Nadezda
N
Kosyakova
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany.
Xiaobo
X
Fan
Department of General, Visceral und Vascular Surgery, Jena University Hospital, Kochstr. 2, Jena, 07743 Germany.
Annelore
A
Altendorf-Hofmann
Department of Biology, Faculty of Science, Khon Kaen University, 123 Moo 16 Mittapap Rd, Khon Kaen, Muang District 40002 Thailand.
Alongklod
A
Tanomtong
Department of Biology, Faculty of Science, Khon Kaen University, 123 Moo 16 Mittapap Rd, Khon Kaen, Muang District 40002 Thailand.
Arunrat
A
Chaveerach
Departamento de Genética e Evolução, Universidade Federal de São Carlos, São Carlos, SP Brazil.
Marcelo Bello
MB
de Cioffi
Instituto Evandro Chagas, Seção de Meio Ambiente, Laboratório de Cultura de Tecidos e Citogenética, Ananindeua, PA Brazil.
Edivaldo
E
de Oliveira
Instituto Evandro Chagas, Seção de Meio Ambiente, Laboratório de Cultura de Tecidos e Citogenética, Ananindeua, PA Brazil.
Joachim-U
JU
Walther
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany.
Thomas
T
Liehr
Institute of Human Genetics, Jena University Hospital, Postfach, 07740, Jena, Germany ; Kinderklinik, Ludwig Maximillians Universität, 80337 Munich, Germany.
Jyoti P
JP
Chaudhuri
Chromosomes; Genome architecture; Haploid grouping; Metaphase; Parental origin