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Background: The outcomes of in vitro fertilization and/or intracytoplasmic sperm injection (IVF/ICSI) are contradictory among individuals with chromosomal polymorphisms.Objectives: To assess whether chromosomal polymorphisms affect the outcomes of assisted reproductive technologies.Search Strategy: Four online databases were searched from inception to September 18, 2017, using terms including "chromosomal polymorphisms" and "In vitro fertilization."Selection Criteria: The meta-analysis included studies published in any language on IVF/ICSI outcomes in relation to male and/or female chromosomal polymorphisms (n=8).Data Collection and Analysis: Data were extracted using a predesigned form. The IVF/ICSI outcomes were then pooled and their heterogeneity assessed.Main Results: Male chromosomal polymorphisms showed lowered values for fertilization rate (odds ratio [OR] 1.29, 95% confidence interval [CI] 1.09-1.54; P=0.004); cleavage rate (OR 2.65, 95% CI 1.88-3.72; P<0.001); good quality embryos rate (OR 1.26, 95% CI 1.15-1.39; P<0.001); and live birth rate (OR 1.42, 95% CI 1.10-1.83; P=0.007). By contrast, early spontaneous abortion rate, clinical pregnancy rate, and ongoing pregnancy rate were not affected in this group. No relationship was found between IVF/ICSI outcomes and female chromosomal polymorphisms.Conclusions: Male, but not female, chromosomal polymorphisms were associated with lowered values for some outcomes of IVF/ICSI. [ABSTRACT FROM AUTHOR]

The CRISPR-Cas9 system is a new targeted nuclease for genome editing, which can directly introduce modifications at the targeted genomic locus. The system utilizes a short single guide RNA (sgRNA) to direct the endonuclease Cas9 in the genome. Upon targeting, Cas9 can generate DNA double-strand breaks (DSBs). As such DSBs are repaired by non-homologous end joining (NHEJ) or homology directed repair (HDR), therefore facilitates introduction of random or specific mutations, repair of endogenous mutations, or insertion of DNA elements. The system has been successfully used to generate gene targeted cell lines including those of human, animals and plants. This article reviews recent advances made in this rapidly evolving technique for the generation of animal models for human diseases.

β-thalassemia is one of the most prevalent inherited hemoglobin disorders. Compound heterozygotes or homozygous mutations of the β-globin chain gene account for severe cases of β-thalassemia that require lifelong transfusion, and make it necessary to identify β-thalassemia carries for prenatal diagnosis. The increase in hemoglobin A2 (HbA2) level is the most significant parameter in the identification of β-thalassemia carriers. HbA2, composing of two α chains and two δ chains, is a minor component of the hemoglobin present in normal adult red blood cells, accounting for about 2.5% of the total hemoglobin in healthy individuals. However, HbA2 level is also elevated in some pregnant women. This study aimed to evaluate the value of HbA2 level in the screening of pregnant women with β-thalassemia trait. Pregnant and non-pregnant women were randomly recruited who attended the prenatal care or diagnosis at our hospital located in Guangdong, a province in South China. Hemoglobin capillary electrophoresis was performed on high performance liquid chromatography to measure HbA2 levels in blood. The β-globin gene mutations were detected by the PCR-reverse dot-blot assay, and some were verified by direct sequencing. Pregnant women (n = 96) and non-pregnant women (n = 114) with normal HbA2 level (< 3.5%) had no β-thalassemia mutation. In contrast, pregnant women (n = 55) and non-pregnant women (n = 85) with elevated HbA2 level (≥ 3.5%) are β-thalassemia carriers. In conclusion, HbA2 level is a good marker for screening β-thalassemia trait in pregnant women in South China population.