by Ivan Y. Iourov  , Svetlana G. Vorsanova  and Yuri B. Yurov

Received: 29 May 2018;  Published: 15 August 2018;  doi: 10.21926/obm.genet.1803028

Runs of homozygosity (ROH) are uninterrupted contiguous regions within the genome exhibiting allelic homozygosity (alleles are inherited from the same parent). Genome-wide analyses consistently demonstrate that megabase-scale ROH are ubiquitous in humans, reflecting individual demographic history. The number and length of ROH correlate increasingly with the degree of consanguinity and can be associated with genetic diseases in both inbred and outbred individuals. Genomic imprinting and uniparental disomy (UPD) are [...]

by Karine Sénécal  , Brigid Unim  and Bartha Maria Knoppers

Received: 19 October 2017;  Published: 14 August 2018;  doi: 10.21926/obm.genet.1803027

The benefits of neonatal screening programs are undeniable: children’s lives are saved, and disease burden and morbidity alleviated. Without a doubt, « classical » neonatal screening programs are in the best interests of newborns. Indeed, those screening programs are recognized among the ten most important public health achievements. However, newborn screening programs raise ethical, legal and social challenges. For example, which criteria should govern whether or not to include a disease in the list of screened co [...]

by Ana Monteagudo-Sánchez  , Marta Sánchez-Delgado  , Sonia Guara Ciurana  , Jose Medrano  , Maria Eugenia Poo-Llanillo  , Miho Ishida  , Gudrun E. Moore  , Isabel Iglesias-Platas  , Carlos Simón  and David Monk

Received: 29 May 2018;  Published: 29 July 2018;  doi: 10.21926/obm.genet.1803026

Background: Symmetrical DNA methylation profiles of autosomal genes are associated with equal expression by both alleles. Genes with an allelic imbalance or monoallelic expression are associated with discrete intervals of allele-specific methylation (ASM), as highlighted by genomic imprinting, X-chromosome inactivation and genotype-driven ASM. However, a more complex pattern has been described in which random monoallelic methylation provides cells with a unique mechanism for modulating allelic dosage. Methods: We c [...]

by Inês Lopes Cardoso

Received: 17 April 2018;  Published: 27 July 2018;  doi: 10.21926/obm.genet.1803025

Some repeats of three or more nucleotides in tandem, which are present in a gene or in its vicinity, tend to increase in number and for this reason are called dynamic mutations. These triplet repeats are unstable and can expand from one generation to the next. According to the expansion size, an unaffected individual can carry a pre-mutation that will expand through generations leading to the development of triplet repeat expansion diseases. The increase in the number of repeats over time leads to earlier developme [...]

by Joep Geraedts

Received: 05 June 2018;  Published: 23 July 2018;  doi: 10.21926/obm.genet.1803024

Both preimplantation genetic testing (PGT) and prenatal diagnosis (PND) are powerful tools to tackle the transmission of inherited disorders carried by families from generation to generation. Here, we present an overview of the current landscape of both methods and identify the pros and cons of each of these reproductive options. In prenatal testing, non-invasive diagnostic methods have become available as an alternative for invasive diagnosis. Different genome sequencing strategies have now been introduced that en [...]

by Irina Bakloushinskaya  and Sergey Matveevsky

Received: 16 May 2018;  Published: 22 July 2018;  doi: 10.21926/obm.genet.1803023

Species of mole voles Ellobius demonstrate a broad variation in sex chromosomes and autosomes, which is unique among mammals. In four species, a Y chromosome was lost, and X0 or XX sex chromosomes in both sexes were obtained. The key testis-determining Sry (Sex-determining Region on Y) gene is absent in these species, and the regulation of its target, the Sox9 (SRY -box 9) gene, is questionable due to deletion in the key enhancer. In a single species, E. fuscocapillus, with routine XX-XY, the same deletion is prese [...]

by Diane B. Paul  and Ilana Löwy

Received: 16 April 2018;  Published: 12 June 2018;  doi: 10.21926/obm.genet.1802022

We address an ongoing controversy over what health-care providers tell prospective parents about Down Syndrome (DS). Many parent, disability-rights, and anti-abortion activists believe that the messages that health-care professionals transmit to pregnant women and their partners are distorted. In their view, OB-GYNs, primary-care providers, clinical geneticists, midwives and other medical professionals generally assume that the quality of life for individuals with DS and their families is poor, whereas in fact, tho [...]

by Thomas Liehr  , Monika Ziegler  , Nadezda Kosyakova  and Ahmed B.H. Al-Rikabi

Received: 16 March 2018;  Published: 17 May 2018;  doi: 10.21926/obm.genet.1802021

Background:Fluorescence in situ hybridization (FISH) can be performed on metaphase- and/or interphase cells. Metaphase cells can exclusively be obtained and studied after time-consuming cell culture. Therefore, this technique is suitable only for cells derived from peripheral blood, bone marrow or fibroblasts, the latter including skin, tumour or "prenatal tissues", such as the amnion or chorion. On the other hand, interphase cells can be gained from many different cells and even without cell culture. Methods:Here, [...]

by Virginie Vignard  and Delphine Fradin

Received: 13 March 2018;  Published: 15 May 2018;  doi: 10.21926/obm.genet.1802020

Melanoma is a highly aggressive skin cancer with high incidence worldwide. There is growing evidence that aberrantly expressed non-coding RNAs (ncRNAs) play a role in the development, progression and dissemination of melanoma tumor cells. Among the many types of ncRNAs described in this review, the functions of micro- and long non-coding RNAs are described and related to the six hallmarks of cancer. Recently, ncRNAs discovered in body fluids have become known as one of the most promising groups of oncological bioma [...]

by Peter Bauer  , Gabriele Wildhardt  , Dieter Gläser  , Clemens Müller-Reible  , Hanno J. Bolz  , Hanns-Georg Klein  , Ulrich Finckh  and Ute Hehr

Received: 24 September 2017;  Published: 28 April 2018;  doi: 10.21926/obm.genet.1802019

On behalf of the German Society of Human Genetics, we present guidelines for molecular genetic diagnostic testing using high-throughput technology, such as next-generation sequencing (NGS). These guidelines have been formulated by an expert group and reviewed by members of the German Society of Human Genetics. Building on the existing EuroGentest guidelines for diagnostic NGS, these updated guidelines incorporate additional aspects and country-specific topics. New considerations include the introduction of a check [...]