Fragile X founder effect and distribution of CGG repeats among the mentally retarded population of Andalusia, South Spain

Phylogenetic analysis of Aceh cattle breed of Indonesia through mitochondrial D-Loop region

The objective of this research was to find the basic data on genetic diversity of mtDNA D-Loop in Aceh cattle and its association with Bhutanese, Chinese, and Indian cattle. There were sixty samples of DNA which had been sequenced; i.e. Banda Aceh (11), Saree (20), and Indrapuri (29). To the best of our knowledge this is the first published data on the complete mitochondrial D-Loop sequence of Aceh cattle. Results show that Aceh cattle have the closest relationship to Bos indicus and have been influenced by Bos taurus. The closest genetic ranges among Aceh cattle, Bhutanese, Chinese, Indian and Zebu were Aceh-Zebu (0.0138), Aceh-Bhutanese (0.0156), Aceh-Chinese (0.0190) and Aceh-Indian (0.0193). D-Loop mtDNA analyses showed that there were 27 haplotypes in which twenty-one samples spread in haplotype 1, two samples were in haplotype 2, and the other four haplotypes had various samples in the range of three to seventeen samples. One sample of Aceh cattle from Saree has a closest maternal genetic with B. taurus. One of the four mutations among the star-shaped clusters on median joining network was a new specific haploid-group in Aceh cattle. From this finding it could be assumed that Aceh cattle form a specific haplotype and it can be conclude that Aceh cattle are animal genetic resources from Aceh in Sumatera Island that have to be preserved.

Epstein-Barr virus transformation of human lymphoblastoid cells from patients with fragile X syndrome induces variable changes on CGG repeats size and promoter methylation

BACKGROUND

Our understanding of fragile X syndrome can be improved by reversing the expression of the silenced fragile X mental retardation 1 (FMR1) gene in immortalized cells from these patients. Epstein-Barr virus (EBV) infection has been extensively used to transform B cells into a permanent lymphoblastoid cell line.

METHODS

We immortalized B lymphocytes from three different fragile X patients and one normal male. We analyzed the CGG triplet repeats and methylation status of the FMR1 and interferon (IFN)-gamma promoter. We also assayed FMR1 mRNA levels by real-time PCR and FMR1 protein (FMRP) by Western blot.

RESULTS

We observed that EBV transformation may induce the instability of CGG repeats and DNA demethylation that can lead to the modification of mRNA expression.

CONCLUSIONS

EBV transformation may induce variable changes in the genome that can lead to the misinterpretations of experimental data obtained from these cells. Thus, periodic testing of DNA from immortalized cells should be routinely undertaken to detect undesired effects.