Quality deficiencies in single nucleotide polymorphism （SNP） analyses have important implications. We used missingness rates to investigate the quality of a recently published dataset containing 424 mitochonddal, 21...Quality deficiencies in single nucleotide polymorphism （SNP） analyses have important implications. We used missingness rates to investigate the quality of a recently published dataset containing 424 mitochonddal, 211 Y chromosomal, and 160 432 autosomal SNPs generated by a semicustom Illumina SNP array from 5 392 dogs and 14 grey wolves. Overall, the individual missingness rate for mitochondrial SNPs was -43.8%, with 980 （18.1%）individuals completely missing mitochondrial SNP genotyping （missingness rate=l）. In males, the genotype missingness rate was -28.8% for Y chromosomal SNPs, with 374 males recording rates above 0.96. These 374 males also exhibited completely failed mitochondrial SNPs genotyping, indicative of a batch effect. Individual missingness rates for autosomal markers were greater than zero, but less than 0.5. Neither mitochondrial nor Y chromosomal SNPs achieved complete genotyping （locus missingness rate=0）, whereas 5.9% of autosomal SNPs had a locus missingness rate=l. The high missingness rates and possible batch effect show that caution and rigorous measures are vital when genotyping and analyzing SNP array data for domestic animals. Further improvements of these arrays will be helpful to future studies.展开更多
Fetal cells can enter maternal blood during pregnancy but whether they can also cross the blood-brain barrier to enter the maternal brain remains poorly understood. Previous results suggest that fetal cells are summon...Fetal cells can enter maternal blood during pregnancy but whether they can also cross the blood-brain barrier to enter the maternal brain remains poorly understood. Previous results suggest that fetal cells are summoned to repair damage to the mother＇s brain. If this is confirmed, it would open up new and safer avenues of treatment for brain damage caused by strokes and neural diseases. In this study, we aimed to investigate whether a baby＇s stem cells can enter the maternal brain during pregnancy. Deceased patients who had at least one male offspring and no history of abortion and blood transfusion were included in this study. DNA was extracted from brain tissue samples of deceased women using standard phenol-chloroform extraction and ethanol precipitation methods. Genomic DNA was screened by quantitative fluorescent-polymerase chain reaction amplification together with short tandem repeat markers specific to the Y chromosome, and 13, 18, 21 and X. Any foreign DNA residues that could be used to interpret the presence of fetal stem cells in the maternal brain were monitored. Results indicated that fetal stem cells can not cross the blood-brain barrier to enter the maternal brain.展开更多
基金supported by grants from the NSFC(91531303)the 973 programs(2013CB8352002013CB835202)
文摘Quality deficiencies in single nucleotide polymorphism （SNP） analyses have important implications. We used missingness rates to investigate the quality of a recently published dataset containing 424 mitochonddal, 211 Y chromosomal, and 160 432 autosomal SNPs generated by a semicustom Illumina SNP array from 5 392 dogs and 14 grey wolves. Overall, the individual missingness rate for mitochondrial SNPs was -43.8%, with 980 （18.1%）individuals completely missing mitochondrial SNP genotyping （missingness rate=l）. In males, the genotype missingness rate was -28.8% for Y chromosomal SNPs, with 374 males recording rates above 0.96. These 374 males also exhibited completely failed mitochondrial SNPs genotyping, indicative of a batch effect. Individual missingness rates for autosomal markers were greater than zero, but less than 0.5. Neither mitochondrial nor Y chromosomal SNPs achieved complete genotyping （locus missingness rate=0）, whereas 5.9% of autosomal SNPs had a locus missingness rate=l. The high missingness rates and possible batch effect show that caution and rigorous measures are vital when genotyping and analyzing SNP array data for domestic animals. Further improvements of these arrays will be helpful to future studies.
基金supported by Research Funds of University of ukurova,Turkey
文摘Fetal cells can enter maternal blood during pregnancy but whether they can also cross the blood-brain barrier to enter the maternal brain remains poorly understood. Previous results suggest that fetal cells are summoned to repair damage to the mother＇s brain. If this is confirmed, it would open up new and safer avenues of treatment for brain damage caused by strokes and neural diseases. In this study, we aimed to investigate whether a baby＇s stem cells can enter the maternal brain during pregnancy. Deceased patients who had at least one male offspring and no history of abortion and blood transfusion were included in this study. DNA was extracted from brain tissue samples of deceased women using standard phenol-chloroform extraction and ethanol precipitation methods. Genomic DNA was screened by quantitative fluorescent-polymerase chain reaction amplification together with short tandem repeat markers specific to the Y chromosome, and 13, 18, 21 and X. Any foreign DNA residues that could be used to interpret the presence of fetal stem cells in the maternal brain were monitored. Results indicated that fetal stem cells can not cross the blood-brain barrier to enter the maternal brain.
