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Supernumerary chromosomes in the black rat (Rattus rattus) and their distribution in three geographic variants

Yosida TH

Cytogenet. Cell Genet., 1977;18(3):149-59.
PMID: 862437

Supernumerary chromosomes have been examined in 352 black rats, covering three geographic variants, by use of conventional and C-band staining techniques. Metacentric supernumerary chromosomes, one to three in number, were found in Malayan black rats (Rattus rattus diardii), with 2n=42, in Indian black rats (R. rattus rufescens), with 2n=38, and in Ceylonese black rats (R. rattus kandianus), with 2n=40. The supernumeraries had similar morphology and stained heavily along their entire length by C-band staining. These findings suggested that the supernumeraries had originally developed in the Asian-type black rats and then were sequentially transmitted to the Ceylonese and Oceanian-type black rats, probably in southwestern Asia. A subtelocentric supernumerary chromosome found in one Japanese black rat seemed to have developed independently from the above metacentric supernumeraries.

Matched MeSH terms: Chromosome Aberrations*
The chromosomes of four species of the nasuta complex of Drosophila. I. Chromosome maps and inversion polymorphism

Lambert DM

J Hered, 1976 3 1;67(2):92-8.
PMID: 5483

The salivary chromosomes of four species of the nasuta complex of Drosophila, D. sulfurigaster albostrigata, D, kohkoa, D. albomicans, and D. kepulauana were studied and chromosome maps of each species are presented; the maps of the latter three species are based on the map of D. sulfurigaster albostrigata. Three of the species D. sulfurigaster albostrigata, D. albomicans, and D. kohkoa were shown to be highly polymorphic for chromosomal inversions while the available evidence indicated that D. kepulauana is much less polymorphic. These facts are correlated with the geographic distribution of the species. Transitional homoselection has not been complete in the evolution of three of the species since D. sulfurigaster albostrigata, D. kohkoa, and D. albomicans have a number of naturally occurring polymorphisms in common.

Matched MeSH terms: Chromosome Aberrations*
Fulltext The role of conventional and molecular cytogenetics in the diagnosis of microdeletion syndromes

Salwati Shuib, Sharifah Noor Akmal, Zarina Abdul Latif, Nor Zarina Zainal Abidin, Zubaidah Zakaria

Medicine & Health, 2006;1(1):45-52.
MyJurnal

In this report we demonstrate the role of fluorescence in situ hybridisation (FISH) and conventional cytogenetic methods in clinically and cytogenetically confirmed cases of microdeletion syndromes. A total of nine cases were referred to the Cytopathology and Cytogenetic Unit, Hospital Universiti Kebangsaan Malaysia (HUKM) from 2002 to 2004. They include three Prader-Willi syndrome, three DiGeorge syndrome, one Williams syndrome, one Miller-Dieker syndrome and one Kallmann syndrome. Blood samples from the patients were cultured and harvested following standard procedures. Twenty metaphases were analysed for each of the cases. FISH analysis was carried out for all the cases using commercial probes (Vysis, USA): SNRPN and D15S10 for Prader-Willi syndrome, LIS1 for Miller Dieker syndrome, ELN for Williams syndrome, KAL for Kallmann syndrome, TUPLE 1 and D22S75 for DiGeorge syndrome. Conventional cytogenetic analysis revealed normal karyotypes in all but one case with structural abnormality involving chromosomes 9 and 22. FISH analysis showed microdeletions in all of the nine cases studied. This study has accomplished two important findings ie. while the FISH method is mandatory in ruling out microdeletion syndromes, conventional cytogenetics acts as a screening tool in revealing other chromosomal abnormalities that may be involved with the disease.

Matched MeSH terms: Chromosome Aberrations
Thyroid autoimmunity and autoimmune thyroid disease in Malaysian girls with Turner syndrome: An understudied population

Lee YL, Zaini AA, Idris AN, Abdullah RA, Wong JS, Hong JS, et al.

J Paediatr Child Health, 2023 Jul;59(7):879-884.
PMID: 37066819 DOI: 10.1111/jpc.16405

AIMS: Knowledge on the spectrum of thyroid disorders amongst Turner syndrome (TS) patients in Southeast Asia is limited. This study aimed to evaluate the prevalence of thyroid autoimmunity, the spectrum of autoimmune thyroid disease and association with age and karyotype amongst Malaysian TS girls.
METHODS: A cross-sectional study was conducted at 11 paediatric endocrine units in Malaysia. Blood samples for antithyroglobulin antibodies, antithyroid peroxidase antibodies and thyroid function test were obtained. In patients with pre-existing thyroid disease, information on clinical and biochemical thyroid status was obtained from medical records.
RESULTS: Ninety-seven TS patients with a mean age of 13.4 ± 4.8 years were recruited. Thyroid autoimmunity was found in 43.8% of TS patients. Nineteen per cent of those with thyroid autoimmunity had autoimmune thyroid disease (Hashimoto thyroiditis in 7.3% and hyperthyroidism in 1% of total population). Patients with isochromosome X and patients with 45,X mosaicism or other X chromosomal abnormalities were more prone to have thyroid autoimmunity compared to those with 45,X karyotype (OR 5.09, 95% CI 1.54-16.88, P = 0.008 and OR 3.41, 95% CI 1.32-8.82, P = 0.01 respectively). The prevalence of thyroid autoimmunity increased with age (33.3% for age 0-9.9 years; 46.8% for age 10-19.9 years and 57.1% age for 20-29.9 years) with autoimmune thyroid disease detected in 14.3% during adulthood.
CONCLUSION: Thyroid autoimmunity was significantly associated with the non 45,X karyotype group, particularly isochromosome X. Annual screening of thyroid function should be carried out upon diagnosis of TS until adulthood with more frequent monitoring recommended in the presence of thyroid autoimmunity.

Matched MeSH terms: Chromosome Aberrations
Fulltext Trisomy X and myelodysplastic syndrome (MDS) with eosinophilia

Eusni, R.M.T., Leong, C.F., Salwa, S.

Malaysian Journal of Medicine and Health Sciences, 2012;8(2):65-67.
MyJurnal

We reported a young patient with myelodysplastic syndrome (MDS) with eosinophilia, in which her chromosomal analysis revealed the presence of trisomy X and a marker chromosome at chromosome 11. The technique used to detect the chromosomal abnormalities is a multicoloured –fluorescent in situ hybridization technique (M-FISH). Our observation suggested that these underlying chromosomal abnormalities were probably responsible for her development of MDS with eosinophilia.
Myelodysplastic syndrome (MDS) is a condition whereby there is ineffective production of haematopoietic stem cells and poor quality of cells produced. The cause can either be a primary bone marrow problem, de novo or therapy related. Most MDS cases are secondary rather than primary. Many chromosomal abnormalities have been found in cases of myelodysplastic syndrome. We described a case of MDS with eosinophilia in association with presence of trisomy X and a marker chromosome in chromosome 11.

Matched MeSH terms: Chromosome Aberrations; Sex Chromosome Aberrations
Whole-Exome Sequencing of ETV6/RUNX1 in Four Childhood Acute Lymphoblastic Leukaemia Cases

Zakaria Z, Othman N, Ismail A, Kamaluddin NR, Esa E, Abdul Rahman EJ, et al.

Asian Pac J Cancer Prev, 2017 04 01;18(4):1169-1175.
PMID: 28548470

Background: ETV6/RUNX1 gene fusion is the most frequently seen chromosomal abnormality in childhood acute
lymphobastic leukamia (ALL). However, additional genetic changes are known to be required for the development of
this type of leukaemia. Therefore, we here aimed to assess the somatic mutational profile of four ALL cases carrying the
ETV6/RUNX1 fusion gene using whole-exome sequencing. Methods: DNA was isolated from bone marrow samples
using a QIAmp DNA Blood Mini kit and subsequently sequenced using the Illumina MiSeq system. Results: We
identified 12,960 to17,601 mutations in each sample, with a total of 16,466 somatic mutations in total. Some 15,533
variants were single nucleotide polymorphisms (SNPs), 129 were substitutions, 415 were insertions and 389 were
deletions. When taking into account the coding region and protein impact, 1,875 variants were synonymous and 1,956
were non-synonymous SNPs. Among non-synonymous SNPs, 1,862 were missense, 13 nonsense, 35 frameshifts, 11
nonstop, 3 misstart, 15 splices disrupt and 17 in-frame indels. A total of 86 variants were located in leukaemia-related
genes of which 32 variants were located in the coding regions of GLI2, SP140, GATA2, SMAD5, KMT2C, CDH17,
CDX2, FLT3, PML and MOV10L1. Conclusions: Detection and identification of secondary genetic alterations are
important in identifying new therapeutic targets and developing rationally designed treatment regimens with less
toxicity in ALL patients.

Matched MeSH terms: Chromosome Aberrations
Fulltext X-treme loss of sequence diversity linked to neo-X chromosomes in filarial nematodes

Mattick J, Libro S, Bromley R, Chaicumpa W, Chung M, Cook D, et al.

PLoS Negl Trop Dis, 2021 Oct;15(10):e0009838.
PMID: 34705823 DOI: 10.1371/journal.pntd.0009838

The sequence diversity of natural and laboratory populations of Brugia pahangi and Brugia malayi was assessed with Illumina resequencing followed by mapping in order to identify single nucleotide variants and insertions/deletions. In natural and laboratory Brugia populations, there is a lack of sequence diversity on chromosome X relative to the autosomes (πX/πA = 0.2), which is lower than the expected (πX/πA = 0.75). A reduction in diversity is also observed in other filarial nematodes with neo-X chromosome fusions in the genera Onchocerca and Wuchereria, but not those without neo-X chromosome fusions in the genera Loa and Dirofilaria. In the species with neo-X chromosome fusions, chromosome X is abnormally large, containing a third of the genetic material such that a sizable portion of the genome is lacking sequence diversity. Such profound differences in genetic diversity can be consequential, having been associated with drug resistance and adaptability, with the potential to affect filarial eradication.

Matched MeSH terms: Chromosome Aberrations