Can fetal fractions in the cell-free DNA test predict the onset of fetal growth restriction?

Objective To investigate the possible predictive value of fetal fraction in the cell-free DNA (cfDNA) test in pregnancies with early- and late-onset fetal growth restriction (FGR). Methods This retrospective study comprised 247 women who were screened using the cfDNA test for aneuploidies during the first or second trimester and had deliveries at our institution from January 2016 to December 2019. The fetal fractions of women with early- (n = 14) and late-onset (n = 83) FGR and those with uncomplicated pregnancies (n = 150) were compared. Results The median fetal fractions for the early-onset FGR, late-onset FGR, and control groups were 5.7 [interquartile range (IQR) 2.65], 7 (IQR 5), and 7.35 (IQR 3.65), respectively. The fetal fractions were significantly lower in the early-onset FGR group than in the late-onset FGR and control groups (P = 0.047 and P = 0.037, respectively). There was no difference in fetal fractions between the late-onset FGR and control groups (P = 1.00). Conclusion As a placenta-related disease, early-onset FGR had lower fetal fractions in the cfDNA test than uncomplicated pregnancies. For clinical use, lower fetal fractions can contribute as a biomarker for screening asymptomatic women for possible placenta-related diseases, such as early-onset FGR. However, more studies are needed to define the "lower" limit.

Evaluation of chromosomal abnormalities and Y-chromosome microdeletions in 1696 Turkish cases with primary male infertility: A single-center study.

OBJECTIVE: The aim of this study was to determine the frequencies of chromosomal abnormalities and Y-chromosome microdeletions in Turkish cases with primary male infertility in a single center. MATERIAL AND METHODS: Chromosomal abnormalities and Y-chromosome microdeletions were investigated in 1696 cases with primary male infertility between 2012 and 2017. Karyotype analyzes and Y-chromosome microdeletions analyzes [azoospermia factor (AZF) regions] were performed in all cases by using standard cytogenetic methods and the multiplex polymerase chain reaction method, respectively. RESULTS: Chromosomal abnormalities were found in 142 cases (8.4%; 142/1696). Y-chromosome microdeletions were detected in 46 cases (2.7%; 46/1696). Y-chromosome microdeletions in the AZFc region were found in 20 of 46 cases (43%). CONCLUSION: This study is one of the few were a large number of cases was studied in Turkey. It indicates that cytogenetic and Y-chromosome microdeletion studies should be conducted in cases with primary male infertility prior to selecting assisted reproductive techniques.

The Efficiency of SNP-Based Microarrays in the Detection of Copy-Neutral Events at 15q11.2 and 11p15.5 Loci.

Prader-Willi, Angelman, Beckwith-Wiedemann, and Russell-Silver are imprinting syndromes. In this study, we aimed to compare the efficiency of single nucleotide polymorphism (SNP) microarray analysis with methylation-specific Multiplex ligation-dependent probe amplification (MS-MLPA) in the detection of uniparental disomy in these syndromes. The patient samples with regions of loss of heterozygosity (LOH), covering 15q11.2 and 11p15.5 critical loci, were analyzed with MS-MLPA to demonstrate the efficiency of SNP microarray in the detection of uniparental disomy (UPD). In a total of seven patients, LOH covering 15q11.2 and 11p15.5 critical loci was detected. Two (28.6%) of these seven patients showed aberrant methylation (suggesting UPD) in MS-MLPA. SNP microarray is a useful tool in the detection of LOH; however, it should be used with caution, since false-positive or false-negative LOH results can be obtained. Although methylation analysis is recommended as the first tier test in the diagnosis of most of the imprinting disorders, combining methylation analysis with SNP microarray can enhance our evaluation process.

First-Line Molecular Genetic Evaluation of Autosomal Recessive Non-Syndromic Hearing Loss.

OBJECTIVE: The aim of this study is to investigate the efficiency of a first-line molecular genetic evaluation approach, in children with deafness. METHODS: Patients who were found to have sensorineural hearing loss by age-appropriate audiological tests were selected for the molecular genetic evaluation. The molecular genetic evaluation was carried out with GJB2 gene sequence analysis and mtDNA m.1555A>G mutation Restriction Fragment Length Polymorphism (RFLP) analysis. Additionally, in a small group of patients, hearing loss Multiplex Ligation-dependent Probe Amplification (MLPA) analysis was done out to identify the possible role of copy number changes. RESULTS: In this Turkish cohort, which included 104 index patients and 78 relatives, 33 (31.7%) had Pathogenic/Likely Pathogenic variants. One or more GJB2 sequence variants were identified in 46 (44.1%) of the 104 index patients. The homozygous c.35delG mutation by itself explained the etiology in 24% of our ARSNHL group. In one (5%) of the 20 patients of MLPA group, a hemizygous deletion in POU3F4 gene was detected. CONCLUSION: In our Turkish cohort, we applied a first-line molecular genetic evaluation approach using GJB2 gene sequence analysis and mtDNA m.1555A>G RFLP analysis. This approach revealed the genetic etiology of 44.1% of our index patients. Additionaly, the results of hearing loss MLPA analysis revealed the limited role of copy number changes in this patient group. Furthermore, with a detailed genotype-phenotype association workup, 2 rare cases of Deafness with Palmoplantar Hyperkeratosis and Keratitis-Ichthyosis-Deafness syndrome were reported.

cfDNA in exhaled breath condensate (EBC) and contamination by ambient air: toward volatile biopsies.

Exhaled breath is a source of volatile and nonvolatile biomarkers in the body that can be accessed non-invasively and used for monitoring. The collection of lung secretions by conventional methods such as bronchoalveolar lavage, induced sputum collection, and core biopsies is limited by the invasive nature of these methods. Non-invasive collection of exhaled breath condensate (EBC) provides fluid samples that are representative of airway lining fluids. Various volatile and nonvolatile biomarkers can be detected in volatile condensates, such as H2O2, nitric oxide, lipid mediators, cytokines, chemokines, DNA, and microRNAs. Studies have examined cell-free DNA (cfDNA) in plasma samples from non-small-cell lung cancer patients, offering to new insights and fostering development of the liquid biopsy. However, few studies have examined cfDNA in EBC samples. This study examined whether EBC is an appropriate source of cfDNA using housekeeping-gene-specific primer probes and quantitative real-time polymerase chain reaction in healthy subjects. Ambient (room) air is contaminated with DNA, so caution is needed. Preliminary studies indicated that volatile biopsies are becoming an important diagnostic tool in lung cancer.

Fetal HLA-G alleles and their effect on miscarriage.

BACKGROUND: Immunosuppression at the feto-maternal interface is crucial for a successful pregnancy outcome. Human leukocyte antigen-G (HLA-G) seems to be a major contributor to fetal tolerance. The HLA-G expression is seen in cytotrophoblasts and in maternal blood. Fetal HLA-G acts on decidual antigen-presenting cells (APCs), natural killers (NKs) and T cells. Recent findings revealed that defects in placentation and their consequences are associated with maternal HLA-G variants and their expression levels. OBJECTIVES: The objective of this article is to investigate the relationship between fetal HLA-G alleles and miscarriage, which has not been investigated to date. MATERIAL AND METHODS: The present study includes 204 recurrent miscarriage (RM) cases who were admitted to our clinic between 2012 and 2016. Twenty-eight miscarriage products without maternal cell contamination and any known pathology were analyzed by HLA-G typing. In addition, 3' untranslated region (UTR) 14-base pair (bp) insertion/deletion polymorphism was also investigated by Sanger sequencing. RESULTS: For our population, the most frequent HLA-G type was G*01:01, both in the study group (30.3%) and in the control group (47%). The study revealed that the G*01:04 allele was significantly associated with miscarriage (p = 0.007). The 3' UTR 14bp deletion was more frequent in the miscarriage group, but there was no significant correlation. CONCLUSIONS: HLA-G alleles seem to be related with miscarriage and should be considered in RM cases.