Complete sequence analysis of mitochondrial DNA of aplastic anemia patients

Abstract

ABSTRACT. This study was primarily undertaken to test the hypothesis that mitochondrial DNA (mtDNA) mutations may be associated with aplastic anemia (AA). We analyzed mtDNA sequences from 15 patients with AA. The samples were obtained from bone marrow, and patients' oral epithelial cells were collected for normal tissue comparison. Total DNA was amplified by PCR after extraction, and these segments were then sent for sequencing. The results were compared with those of oral epithelial tissues as well as mtDNA sequences in the revised Cambridge Reference Sequence (rCRS) database. We detected 61 heteroplasmic mutations in 11 genes, including those encoding NADH dehydrogenase (ND)1-2 and 4-6, tRNA glutamic acid (TRNE), ribosomal RNA (RNR) 1 and 2, cytochrome c oxidase (COX1), cytochrome b (CYTB), and tRNA glycine (TRNG); mutation rates were particularly high in ND2 2131©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 11 (3): 2130-2137 (2012) Mitochondrial DNA mutation in aplastic anemia (34.4%) and ND4 (21.3%) in the patients' mtDNA genomes. The products of these genes are involved in oxidation in the respiratory chain, and a large number of homoplasmic mutations were found. Interestingly, these 162 polymorphisms were mostly in the D-loop DNA structure (54.3%), in which numerous mutations associated with leukemia and myelodysplastic syndromes are found. We conclude that functional impairment of the mitochondrial respiratory chain induced by mutation may be an important reason for hematopoietic failure in AA patients.

Abnormal metabolites related to bone marrow failure in aplastic anemia patients

“…Cells with an inadequate ATP supply may have difficulties in the properly segregation of chromo somes during mitosis. These factors may decrease energy metabolism, which can affect the self-renewal and differentiation of HSCs (Zhang and Sadek, 2014).The main site of energy metabolism is the mitochondria, and we recently found (Cui et al, 2012) that mutations of mtDNA may induce apoptosis through the mitochondrial pathway.…”

Longevity-associated mitochondrial DNA 5178 C/A polymorphism modulates the effects of coffee consumption on erythrocytic parameters in Japanese men: an exploratory cross-sectional analysis

“…Cui et al . reported that mitochondrial DNA mutations were associated with aplastic anemia [39]. They found that mutation rates were particularly high in the ND2 coding region in the mitochondrial DNA genomes of patients with aplastic anemia.…”

Letter to the Editor Mitochondrial DNA mutations may not be frequent in patients with aplastic anemia - Genet. Mol. Res. 11 (3): 2130-2137 “Complete sequence analysis of mitochondrial DNA of aplastic anemia patients”

“…Considering the si�e of the PCR products presented in Table 2 Cui et al (2012), apparently the authors did not take into account the possibility that PCR products greater than 2000 bp would be difficult to sequence because the concentration of DNA that would be analy�ed would normally be too low (Pareek et al, 2011). Generally, 24 overlapping fragments using sets of he light-strand and heavy-strand oligonucleotide primers are needed to amplify the mitochondrial genome (Rieder et al, 1998).…”

“…Dear Editor, In a recent report, Cui et al (2012) analy�ed the complete sequences of the mitochon-(2012) analy�ed the complete sequences of the mitochondrial genome of patients with aplastic anemia (AA). They concluded that (mtDNA) mutations are more frequent in patients with AA.…”

“…First, Cui et al (2012) studied 15 patients with AA and collected the oral epithelial cells from these patients as controls to analy�e the potential pathogenic mtDNA mutations associated with AA. However, a case-control study is an analytical study, which compares individuals who have a specific disease (cases) with a group of individuals without the disease (controls) (Porta, 2008).…”