Closely related species share large genomic segments called syntenic regions, where the genomic elements such as genes are arranged co-linearly among the species. While synteny is an important criteria in establishing orthologous regions between species, non-syntenic regions may display species-specific features. As the first step in cataloging human- or primate-specific genomic elements, we surveyed human genomic regions that are not syntenic with any other non-primate mammalian genomes sequenced so far. Based on the data compiled in Ensembl databases, we were able to identify 10 such regions located in eight different human chromosomes. Interestingly, most of these highly human- or primate-specific loci are concentrated in subtelomeric or pericentromeric regions. It has been reported that subtelomeric regions in human chromosomes are highly plastic and filled with recently shuffled genomic elements. Pericentromeric regions also show a great deal of segmental duplications. Such genomic rearrangements may have caused these large human- or primate-specific genome segments.
Cataloging ; Chromosomes, Human ; Genome ; Genome, Human ; Humans ; Plastics ; Resin Cements ; Segmental Duplications, Genomic ; Synteny

A new clinico-pathological entity in which isochromosome 17q is the sole abnormality has been reported in myelodysplastic syndrome and in myeloproliferative neoplasm with an aggressive course; In particular, myelodysplastic syndrome with the isolated i(17)(q10) chromosome has the unique features of male sex, severe anemia, dysmegakaryocytic hyperplasia, increased micromegakaryocytes, basophilia, eosinophila and high risk for progression to acute myeloid leukemia (AML). However, the isolated i(17)(q10) is occurring at a relatively low frequency in de novo AML, and only a few reports are available in the literature about the clinical features and molecular characteristics of the isolated i(17)(q10) in AML. Herein, we report both the clinico-pathological features and the results of high resolution single nucleotide polymorphism (SNP) array analysis in a case of AML with i(17)(q10) as the sole cytogenetic abnormality. This case showed marrow findings of basophilia and dysmegakaryocytic hyperplasia and aggressive clinical outcome and these findings were suggestive of the presence of underlying myelodysplastic syndrome. The breakpoint of i(17)(q10) was located within 17p11.2 sub-band, which is known as a genetically highly unstable region presenting a unique genomic architectural features of low copy repeats (LCRs); thus, LCRs within 17p11.2 might lead to genomic instability and facilitate somatic genetic rearrangements such as i(17) (q10) and could play an important pathogenetic role in presenting unique clinico-pathologic features as well as in tumor development and disease progression.
Anemia ; Bone Marrow ; Chromosome Aberrations ; Cytogenetics ; Disease Progression ; Genomic Instability ; Humans ; Hyperplasia ; Isochromosomes ; Leukemia, Myeloid, Acute ; Male ; Myelodysplastic Syndromes ; Polymorphism, Single Nucleotide ; Segmental Duplications, Genomic

segmental duplication, inversion, translocation). Until recently SNPs were thought to be the main source of genetic and phenotypic human variation. However, the use of methods such as array comparative genomic hybridization (array CGH) and fluorescence in situ hybridization (FISH) have revealed the presence of copy number variations(CNVs) ranging from kilobases (kb) to megabases (Mb) in the human genome. There is great interest in the possibility that CNVs play a role in the etiology of common disease such as HIV-1/AIDS, diabetes, autoimmune disease, heart disease and cancer. The discovery of widespread copy number variation in human provides insights into genetic variability among populations and provides a foundation for studies of the contribution of CNVs to evolution and disease.]]>
Coat Protein Complex I ; Comparative Genomic Hybridization ; Diabetes Mellitus, Type 1 ; DNA ; DNA Methylation ; DNA Transposable Elements ; Epigenomics ; Fluorescence ; Genetic Variation ; Genome, Human ; Heart Diseases ; Humans ; In Situ Hybridization ; Polymorphism, Single Nucleotide ; Segmental Duplications, Genomic ; Tandem Repeat Sequences