Human embryos harbor complex mosaicism with broad presence of aneuploid cells during early development.

Pre-implantation genetic testing for aneuploidy (PGT-A) is used in approximately half of in vitro fertilization cycles. Given the limited understanding of the genetics of human embryos, the current use of PGT-A is based on biologically uncertain assumptions and unvalidated guidelines, leading to the possibility of disposing of embryos with pregnancy potential. We isolated and sequenced all single cells (1133) from in vitro cultured 20 human blastocysts.

Development of a PCR-based method to identify fetal sex during IVF cycles.

One of the most recognizable cases of preimplantation genetic diagnosis (PGD) is X-linked diseases. Diagnosis of fetal sex is essential for couples who are known to be at risk of some X-linked disorders. The objective of this study was to discriminate between female (XX) and male (XY) embryos by detecting sex chromosomes-specific sequences in spent culture medium and comparing these results to PGD/CGH array results.

Reproductive options and genetic testing for patients with an inherited cardiac disease.

In the past decade, genetic testing for cardiac disease has become part of routine clinical care. A genetic diagnosis provides the possibility to clarify risk for relatives. For family planning, a genetic diagnosis provides reproductive options, including prenatal diagnosis and preimplantation genetic testing, that can prevent an affected parent from having a child with the genetic predisposition.

Differences in preimplantation blastocyst chromosomal aberrations between polycystic ovary syndrome women and controls: a multi-center retrospective cohort study.

Purpose: Comprehensive chromosomal status of blastocyst from women with polycystic ovary syndrome (PCOS) was limited. This study aimed to identify possible differences in the preimplantation blastocyst chromosome aberrations between PCOS women and controls receiving preimplantation genetic testing (PGT).

Methods: This was a multi-center retrospective cohort study including a total of 707 blastocysts from 147 PCOS women and 3006 blastocysts from 821 control women receiving PGT between 2015 and 2021.

Identification of a pathogenic variant and pre-implantation genetic testing for a Chinese family affected with split-hand/foot malformation.

Split-hand/foot malformation is a serious congenital limb malformation characterized by syndactyly and underdevelopment of the phalanges and metatarsals. In this study, we reported a case of a fetus with hand-foot cleft deformity. Whole exome and Sanger sequencing were used to filter out candidate gene mutation sites and provide pre-implantation genetic testing(PGT) for family members.

Technically feasible solutions to challenges in preimplantation genetic testing for thalassemia: experiences of multiple centers between 2019 and 2022.

Purpose: In clinical practice, the success of preimplantation genetic testing for monogenic diseases (PGT-M) for thalassemia was hindered by the absence of probands, incomplete family members, or failure in detecting embryonic gene mutation sites. This study aimed to address these issues.

Methods: This retrospective study included 342 couples undergoing PGT-M for α- or β-thalassemia at three reproductive medicine centers from 2019 to 2022.

The impact of blastocyst grade on singleton birth weight in fresh IVF‒ET cycles in ART: a retrospective study.

Background: The positive correlation between embryo quality and pregnancy outcomes has been confirmed in many studies, but there are few on the impact of embryo quality on neonatal weight, especially among neonates from fresh IVF‒ET cycles in ART. Therefore, this study aimed to compare the birth weights of infants from different blastocyst grades in fresh IVF-ET cycles and explore related factors affecting birth weight.

Methods: The main outcome measure was singleton birth weight.

Clinical-grade whole genome sequencing-based haplarithmisis enables all forms of preimplantation genetic testing.

High-throughput sequencing technologies have increasingly led to discovery of disease-causing genetic variants, primarily in postnatal multi-cell DNA samples. However, applying these technologies to preimplantation genetic testing (PGT) in nuclear or mitochondrial DNA from single or few-cells biopsied from in vitro fertilised (IVF) embryos is challenging. PGT aims to select IVF embryos without genetic abnormalities.

A Novel Heterozygous Intronic FBN1 Variant Contributes to Aberrant RNA Splicing in Marfan Syndrome.

Background: Marfan syndrome (MFS) is a complex genetic systemic connective tissue disorder. It is well known that genetic factors play a critical role in the progression of MFS, with nearly all cases attributed to variants in the FBN1 gene.

Methods: We investigated a Chinese family with MFS spanning two generations.

Comparison of aneuploidy for patients of different ages treated with progestin-primed ovarian stimulation or GnRH antagonist protocols.

Research Question: Does euploidy status differ among patients of different ages treated with progestin-primed ovarian stimulation (PPOS) or gonadotrophin releasing hormone antagonist (GnRH-a) protocols?

Design: Patients undergoing PGT-A (n = 418; 440 cycles) were enrolled and grouped according to female age (<35 years and ≥35 years). Protocols were as follows: PPOS: <35 years (n = 131; 137 cycles); ≥35 years (n = 72; 80 cycles); GnRH-a: <35 years (n = 149; 152 cycles); ≥35 years (n = 66; 71 cycles).

Results: For cycles treated with PPOS in the older group, rates of euploid blastocyst per metaphase Ⅱ oocyte (15.

[Genetic analysis and PGT-SR outcome of a male carrier of exceptional complex chromosome rearrangement].

Objective: To investigate the clinical and genetic characteristics of a male carrier of exceptional complex chromosome rearrangement (CCR) and the outcome of preimplantation genetic testing for chromosomal structural rearrangement (PGT-SR).

Methods: Using the modified high resolution G banding technique and whole-genome low-coverage sequencing (WGLCS), we analyzed the cellular karyotype and molecular karyotype of a male carrier of CCR, performed an analysis of the single-sperm chromosome copy number and conducted PGT-SR for the patient by next-generation sequencing (NGS). In addition, we reviewed the literature on reported male carriers of CCRs and summarized their normal/balanced sperm ratios and PGT-SR outcomes.

[Application of single-sperm sequencing in resolving the carrier status of preimplantation genetic testing for chromosomal structural rearrangements in Robertsonian translocations].

Objective: To investigate the application value of single-sperm sequencing in resolving the carrier status of preimplantation genetic testing (PGT) for chromosomal structural rearrangements in Robertsonian translocations.

Methods: Haplotypes were constructed by single-sperm isolation combined with single-sperm sequencing for a patient with 45, XY, der(13; 14)(q10; q10). Twenty single-sperm samples were isolated by mechanical braking and subjected to whole-genome amplification (WGA), and then the Asian Screening Array (ASA) gene chip was used to detect the 183 708 single nucleotide polymorphisms (SNP) of the WGA products.

[Genetic analysis of carriers of complex chromosome rearrangement].

Objective: To comprehensively analyze the numbers of involved chromosomes and breakpoints and the clinical phenotypes of the patients with complex chromosome rearrangement (CCR).

Methods: We selected 23 745 patients with abnormal fertility seeking medical care in the Center of Reproductive Medicine of Peking University Third Hospital from 2011 to 2015, and analyzed their peripheral blood chromosomal karyotypes using G-banding, C-banding and fluorescence in situ hybridization (FISH).

Results: A total of 28 CCR carriers (0.