A novel EDA variant causing X-linked hypohidrotic ectodermal dysplasia: Case report

Hereditary ectodermal dysplasias are a complex group of inherited disorders characterised by abnormalities in two or more ectodermal derivatives (skin, nails, sweat glands, etc.). There are two main types of these disorders – hidrotic and hypohidrotic/anhidrotic ectodermal dysplasias. Hypohidrotic ectodermal dysplasia (HED) or Christ-Siemens-Touraine syndrome (OMIM: 305100) occurs in 1 out of 5000–10,000 births [19] and has an X-linked recessive inheritance pattern (X-linked hypohydrotic ectodermal dysplasia – XLHED) [2].

The main cause of XLHED is a broad range of pathogenic variants in the EDA gene (HGNC:3157, Xq12-13) which encodes the transmembrane protein ectodysplasin-A [4]. We report here the case of a patient with a novel inherited allelic variant in the EDA gene – NM_001399.5:c.337C>T (p.Gln113*) – in the heterozygous state. Targeted family member screening was conducted and other carriers of this EDA gene pathogenic variant were identified and phenotypically characterised. The patient subsequently underwent in vitro fertilisation with preimplantation genetic testing for monogenic diseases (PGT-M).

Evaluation of embryo aneuploidy (PGT-A) and endometrial receptivity (ERA) testing in patients with recurrent implantation failure in ICSI cycles

OBJECTIVE

The objective of a study was to assess the ability of the pre-implantation genetic testing of embryos for aneuploidy (PGT-A) and Endometrial receptivity array (ERA)-alone or in combination to improve the clinical outcomes in intracytoplasmic sperm injection (ICSI) cycles in patients with repeated implantation failure (RIF).

METHODS

This was a retrospective study of the 253 cycles with a history of the previous RIF. They were divided into four groups: Group I - frozen embryo transfers without any additional tests or procedures (pure FET), n = 72 cycles; Group II - FET with PGT-A, n = 87; Group III - FET with PGT-A and ERA, n = 72; Group IV - FET with ERA, n = 22.

RESULTS

Median age of the entire study group for the females was 35 years. Only Group II (FET + PGT-A) showed statistically significant higher chance in achieving both biochemical (p = .01, OR = 5.5) and clinical pregnancy (p =.049, OR = 2.3), as compared to the Group I (FET with no additional tests). Both Group III and Group IV failed to demonstrate better clinical outcomes as compared to the Group I.

CONCLUSIONS

Patients with RIF can benefit from testing for embryo aneuploidy using the PGT-A method, but the ability of the ERA test to improve the clinical outcome in ICSI cycles seems to be rather limited. Although the endometrium cycle is also weakened with age, the contribution of the embryo genetic quality is evidently more important for successful implantation, although in principle both factors reflect the reproductive health.

Prevalence of testosterone deficiency among aging men with and without morbidities

In this cross-sectional study 1852 men aged 40-70 years attending primary health care were invited to fill out the aging male symptoms (AMS) scale. Out of these, 1222 men were found positive for the AMS and agreed to provide blood samples for the general blood test, lipid profile, glucose levels, and assessment of both total and free testosterone (T) levels. Men were screened for the following morbidities and syndromes: dyslipidemia, arterial hypertension, obesity, type II diabetes, metabolic syndrome, and chronic obstructive pulmonary disease (COPD). Testosterone deficiency was diagnosed if total T ≤ 3.46 ng/mL or free T ≤ 72 pg/mL. Among all 1222 men with positive AMS, decreased blood testosterone levels were detected in 669 men (55%). A total of 402 men were found healthy and 820 men were detected with different morbidities. Out of 669 men with testosterone deficiency, only 2.8% had no co-morbidities and 97.2% were men with co-morbidities. Testosterone levels were found significantly higher among healthy men (median 4.7 ng/mL) as compared to the men with morbidities (median 2.55 ng/mL, p<.001), adjusted for age. Testosterone deficiency was detected in significantly lower proportion of 402 men without co-morbidities as compared to the 820 men with co-morbidities: in 19 men (4.7) and in 650 men (79.3%, p<.05), respectively.

Reducing misdiagnosis caused by maternal cell contamination in genetic testing for early pregnancy loss

The analysis of products of conception (POC) is clinically important to establish the cause of early pregnancy loss. Data from such analyses can lead to specific interventions in subsequent natural or assisted conceptions. The techniques available to examine the chromosomal composition of POC have limitations and can give misleading results when maternal cell contamination (MCC) is overlooked. The aim of this study was to develop a protocol for MCC assessment and to formulate POC material handling, testing, and reporting recommendations. Using array comparative genomic hybridization, we tested 86 POC samples, of which 47 sample pairs (DNA extracted from the POC sample and maternal DNA) were assessed for the presence of MCC. MCC was evaluated using an approach we developed, which exploited the genotyping of 14 STR, AMEL, and SRY loci. POC samples showing the clear presence of villi (63.9%) did not contain any signs of the maternal genome and can therefore be reliably tested using conventional methods. The proportion of 46,XX karyotype in the unselected sample batch was 0.39, which fell to 0.23 in visually good samples and was 0.27 in samples having no signs of contamination upon MCC testing. MCC assessment can rescue visually poor samples from being discarded or wrongly genotyped. We demonstrate here that classification based on visual POC material evaluation and MCC testing leads to predictable and reliable POC genetic testing outcomes. Our formulated recommendations covering POC material collection, transportation, primary and secondary processing, as well as the array of pertinent considerations discussed here, can be implemented by laboratories to improve their POC genetic testing practices. We anticipate our protocol for MCC assessment and recommendations will help reduce the misconception regarding the etiology of miscarried fetuses and foster informed decision-making by clinicians and patients dealing with early pregnancy loss.

The Correlation Between Abnormal Uterine Artery Flow in the First Trimester and Genetic Thrombophilic Alteration: A Prospective Case-Controlled Pilot Study

INTRODUCTION

Evaluation of the first trimester uterine artery flow can predict the development of obstetrical complications. A genotype, making women prone to microthrombi. constitutes the main known susceptibility factor for anomalous development of placenta. Our aim was to study whether polymorphisms of 10 genes leading to blood clotting abnormalities are related to abnormal uterine artery blood flow in the first trimester, and may predict placenta-related diseases.

MATERIAL AND METHODS

In primary analyses we included 19 singleton pregnancies with abnormal blood flow in the uterine arteries during the first trimester of gestation, and 24 matched control with normal flow patterns. All patients were genotyped for sequence variations in F5, F2, F11, MTHFR, SERPINE-1, CYP4V2, SELE, GP6, angiotensinogen (AGT) and fibrinogen gamma (FGG) genes and followed up until delivery.

RESULTS

There were no differences between groups regarding selected sequence variations in any of these genes. The co-occurrence of several polymorphisms in the same patient was also not related to the blood flow patterns in the uterine arteries.

CONCLUSIONS

Although we found certain trends of genetic polymorphisms being related to preeclampsia and fetal growth, we failed to find an association between clotting gene polymorphisms, single or in combination, with the abnormal uterine flow in the first trimester.

The outcomes after transfers of embryos with chromosomal mosaicism: a single reproductive medicine center experience at iVF Riga clinic

Aim: The aim of this study is to summarize the outcomes of transfers of mosaic embryos, which were classified according to guidelines and in strong collaboration of reproductologists, clinical geneticists and patients approved as suitable for transfer. Material and Methods: Retrospective data were collected from 70 patients from a private IVF center to whom embryos with mosaic changes in chromosomal material were transferred from 2015 to 2019. Results and Conclusion: Implantation outcomes and continuing pregnancies showed slight differences, when compared to fully normal embryos. Artifacts have to be differentiated from undeniable aberrations, and correct interpretation of results must be done with following patient counselling and prenatal testing if necessary.

The application of PGT-A for carriers of balanced structural chromosomal rearrangements

The aim of this study was to analyze differences in chromosomal aberrations and euploidy in embryos of each translocation type and gender of carrier in the case series of 10 couples with balanced translocations who underwent IVF with embryos trophectoderm (TE) biopsy and PGT-A to detect chromosomal aberrations. This is a Case Series (Retrospective study). In each case, controlled ovarian hyperstimulation, oocyte insemination with intracytoplasmic sperm injection (ICSI) and cultivation gave multiple blastocysts, that underwent trophectoderm (TE) biopsy with PGT-A analysis using aCGH and NGS. Number of total unbalanced translocations compared to the number of sporadic aneuploid embryos was 39.6% to 39.6% (50% to 50% of all 37 aneuploid embryos). The highest euploidy rate was in male carrier group - 26.7% and the lowest in the Robertsonian translocation carrier group - 18.2%. Sporadic aneuploidy - 68.2% was highest in Robertsonian translocation carrier group and lowest in female group - 11.1%. Chromosomal aberrations related to translocation were highest in female carrier group - 77.8% and lowest in Robertsonian translocation carrier group - 13.6%. Our study showed that expectancy of total embryo aneuploidy rates will be higher in carriers, than in people with normal karyotype. The prevalence of chromosomal aberrations related to translocation was 4.5 times higher in Reciprocal carrier group than in Robertsonian translocation carrier group. Among maternal and paternal carrier groups, the embryos from female carriers had the lowest euploidy rate, unbalanced translocation rate 4.7 times higher than in the male carrier group and higher total aneuploidy rates.

Performance comparison of two whole genome amplification techniques in frame of multifactor preimplantation genetic testing

PURPOSE

To compare multiple displacement amplification and OmniPlex whole genome amplification technique performance during array comparative genome hybridization (aCGH), Sanger sequencing, SNaPshot and fragment size analysis downstream applications in frame of multifactor embryo preimplantation genetic testing.

METHODS

Preclinical workup included linked short tandem repeat (STR) marker selection and primer design for loci of interest. It was followed by a family haplotyping, after which an in vitro fertilization preimplantation genetic testing (IVF-PGT) cycle was carried out. A total of 62 embryos were retrieved from nine couples with a confirmed single gene disorder being transmitted in their family with various inheritance traits-autosomal dominant (genes-ACTA2, HTT, KRT14), autosomal recessive (genes-ALOX12B, TPP1, GLB1) and X-linked (genes-MTM1, DMD). Whole genome amplification (WGA) for the day 5 embryo trophectoderm single biopsies was carried out by multiple displacement amplification (MDA) or polymerase chain reaction (PCR)-based technology OmniPlex and was used for direct (Sanger sequencing, fragment size analysis, SNaPshot) and indirect mutation assessment (STR marker haplotyping), and embryo aneuploidy testing by array comparative genome hybridization (aCGH).

RESULTS

Family haplotyping revealed informative/semi-informative microsatellite markers for all clinical cases for all types of inheritance. Indirect testing gave a persuasive conclusion for all embryos assessed, which was confirmed through direct testing. The overall allele dropout (ADO) rate was higher for PCR-based WGA, and MDA shows a better genomic recovery scale. Five euploid embryos were subjected to elective single embryo transfer (eSET), which resulted in four clinical pregnancies and birth of two healthy children, which proved free of disease causative variants running in the family postnataly.

CONCLUSIONS

A developed multifactor PGT protocol can be adapted and applied to virtually any genetic condition and is capable of improving single gene disorder preimplantation genetic testing in a patient-tailored manner thus increasing pregnancy rates, saving costs and increasing patient reliability.

A New Baltic Population-Specific Human Genetic Marker in the PMCA4 Gene

OBJECTIVES

The PMCA gene family consists of 4 genes and at least 21 splice variants; among these, the Ca2+ ATPase 4 (PMCA4) gene encodes a plasma membrane protein abundantly expressed in several tissues, including the kidney, heart, and sperm. Knockout of PMCA4 causes infertility due to immotile sperm in mouse models. We therefore investigated variants in this gene for potential association with infertility in groups of Estonian (n = 191) and Latvian (n = 92) men with reduced sperm motility.

METHODS

All exons, exon-intron boundaries, 5' and 3' untranslated regions, and the promoter region of the PMCA4 gene were analysed by direct sequencing for a group of Estonian infertile men. Genotyping of guanine and adenine alleles of rs147729934 was performed, using a custom-designed TaqMan® probe for a group of Latvian infertile men as well as additional groups from Latvia and several groups of people with proven ethnicity from the Baltic region.

RESULTS

Although we did not identify any significant associations between variants in the gene and infertility, our results indicated that in all studied Latvian and Estonian groups the adenine allele of the variant rs147729934 was present at a higher frequency than expected. Analysis of additional samples indicated that the adenine allele of rs147729934 likely originated once in the modern-day Baltic or western Russia area, as the frequency of the minor adenine allele observed in this region is remarkably higher than that in the general European population.

CONCLUSIONS

Our results revealed no significant difference in frequencies of genetic variants in PMCA4 gene between men with normal and those with reduced sperm motility. The adenine allele of the variant rs147729934 is potentially an informative tool for future population studies concerning ancient Baltic and Finno-Ugric history.

First preimplantation genetic testing case for monogenic disease in Latvia

Huntington's disease (HD) is fatal neurodegenerative disease caused by a (CAG) triplet repeat expansion in the Huntingtin (HTT) gene. Inheritance pattern of the disease is autosomal dominant and onset depending on triplet repeat count. Transgenerational HD transmission can be avoided by preimplantation genetic diagnosis (PGD). Here, we report the first preimplantation genetic testing case for monogenic disease, in Latvia. The result of our work led to the birth of healthy child with normal HTT alleles in his genome. We describe a PGD strategy and testing algorithm that can be applied to any couple at risk of transmitting monogenic disease.