Genetic disorders and spermatogenesis

Male infertility affects one man in twenty and a genetic basis seems likely in at least 30% of those men. Genetic regulation of fertility involves the inter-related processes of testicular development, spermatogenesis (involving germ cell mitosis, meiosis and spermatid maturation), and their endocrine and paracrine regulation. In regard to spermatogenesis, particular attention has been given to the Yq11 region, where some spermatogenesis genes (‘azoospermia factors’) appear to be located. Several candidate genes have been identified but have not been shown to have a defined or essential role in spermatogenesis. Microdeletions of Yq11 are found in ~15% of azoospermic or severely oligospermic men. The complexity of the genetic control of male fertility is demonstrated by the evidence for genes involved in spermatogenesis and sexual differentiation on the X chromosome and autosomes. Better understanding of the genetic regulation of normal spermatogenesis will provide new probes for clinical studies; however, at present the majority of spermatogenic failure remains without an identified genetic linkage. The advent of intracytoplasmic sperm injection permits fertility in many previously sterile men and presents the possibility of their transmission of infertility; appropriate counselling is required.

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Transcriptomic and genomic variants between koala populations reveals underlying genetic components to disorders in a bottlenecked population

Conservation Genetics ◽

10.1007/s10592-021-01340-7 ◽

2021 ◽

Author(s):

R. E. Tarlinton ◽

J. Fabijan ◽

F. Hemmatzadeh ◽

J. Meers ◽

H. Owen ◽

...

Keyword(s):

Genetic Basis ◽

Genetic Disorders ◽

South Australia ◽

Differentially Expressed ◽

Brain Diseases ◽

Fixation Index ◽

Testicular Development ◽

Genetic Components ◽

Anion Transporter ◽

Two Populations

AbstractHistorical hunting pressures on koalas in the southern part of their range in Australia have led to a marked genetic bottleneck when compared with their northern counterparts. There are a range of suspected genetic disorders such as testicular abnormalities, oxalate nephrosis and microcephaly reported at higher prevalence in these genetically restricted southern animals. This paper reports analysis of differential expression of genes from RNAseq of lymph nodes, SNPs present in genes and the fixation index (population differentiation due to genetic structure) of these SNPs from two populations, one in south east Queensland, representative of the northern genotype and one in the Mount Lofty Ranges South Australia, representative of the southern genotype. SNPs that differ between these two populations were significantly enriched in genes associated with brain diseases. Genes which were differentially expressed between the two populations included many associated with brain development or disease, and in addition a number associated with testicular development, including the androgen receptor. Finally, one of the 8 genes both differentially expressed and with a statistical difference in SNP frequency between populations was SLC26A6 (solute carrier family 26 member 6), an anion transporter that was upregulated in SA koalas and is associated with oxalate transport and calcium oxalate uroliths in humans. Together the differences in SNPs and gene expression described in this paper suggest an underlying genetic basis for several disorders commonly seen in southern Australian koalas, supporting the need for further research into the genetic basis of these conditions, and highlighting that genetic selection in managed populations may need to be considered in the future.

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Genetic Basis of Male Infertility

Anwer Khan Modern Medical College Journal ◽

10.3329/akmmcj.v4i1.13683 ◽

2013 ◽

Vol 4 (1) ◽

pp. 37-39 ◽

Cited By ~ 3

Author(s):

Mosammat Rashida Begum ◽

Mariya Ehsan

Keyword(s):

Genetic Testing ◽

Male Infertility ◽

Medical Treatment ◽

Intracytoplasmic Sperm Injection ◽

Chromosomal Abnormality ◽

Genetic Disease ◽

Genetic Basis ◽

Common Cause ◽

Near Future ◽

Spermatogenic Failure

Infertility is a couple's problem. Almost 50% case males are responsible for infertility. Most common cause is oligospermia and azoospermia and approximately 5% to 15% of men with azoospermia and severe oligospermia may have a chromosomal abnormality. Men with significant spermatogenic compromise are the candidates of intracytoplasmic sperm injection (ICSI). Raised FSH level above 9 is an indication of spermatogenic compromise. So, medical treatment for these patients is waste of time and money. Early attempt of assisted reproduction is ideal to avoid the crisis of total spermatogenic failure in near future. But before going for ICSI genetic testing if possible and proper counseling about possibilities of transmission of genetic disease to offspring is necessary. DOI: http://dx.doi.org/10.3329/akmmcj.v4i1.13683 AKMMC J 2013: 4(1): 37-39

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Reaching Future Scientists, Consumers, & Citizens

The American Biology Teacher ◽

10.1525/abt.2014.76.6.5 ◽

2014 ◽

Vol 76 (6) ◽

pp. 379-383 ◽

Cited By ~ 3

Author(s):

Melissa A. Hicks ◽

Rebecca J. Cline ◽

Angela M. Trepanier

Keyword(s):

Personalized Medicine ◽

Genetic Basis ◽

Genetic Disorders ◽

Single Gene ◽

Personal Health ◽

Adult Onset ◽

Biology Textbooks ◽

Multifactorial Diseases ◽

Single Gene Disorders

An understanding of how genomics information, including information about risk for common, multifactorial disease, can be used to promote personal health (personalized medicine) is becoming increasingly important for the American public. We undertook a quantitative content analysis of commonly used high school textbooks to assess how frequently the genetic basis of common multifactorial diseases was discussed compared with the “classic” chromosomal–single gene disorders historically used to teach the concepts of genetics and heredity. We also analyzed the types of conditions or traits that were discussed. We identified 3957 sentences across 11 textbooks that addressed multifactorial and “classic” genetic disorders. “Classic” gene disorders were discussed relatively more frequently than multifactorial diseases, as was their genetic basis, even after we enriched the sample to include five adult-onset conditions common in the general population. Discussions of the genetic or hereditary components of multifactorial diseases were limited, as were discussions of the environmental components of these conditions. Adult-onset multifactorial diseases are far more common in the population than chromosomal or single-gene disorders; many are potentially preventable or modifiable. As such, they are targets for personalized medical approaches. The limited discussion in biology textbooks of the genetic basis of multifactorial conditions and the role of environment in modifying genetic risk may limit the public’s understanding and use of personalized medicine.

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High-Density Genetic Linkage Map Construction Using Whole-Genome Resequencing for Mapping Qtls of Resistance to Aspergillus Flavus Infection in Peanut

10.21203/rs.3.rs-538664/v1 ◽

2021 ◽

Author(s):

Yifei Jiang ◽

Huaiyong Luo ◽

Bolun Yu ◽

Yingbin Ding ◽

Yanping Kang ◽

...

Keyword(s):

Linkage Map ◽

Aspergillus Flavus ◽

Genetic Linkage ◽

Genetic Basis ◽

Genetic Linkage Map ◽

Aflatoxin Contamination ◽

Whole Genome ◽

Genome Resequencing ◽

Favorable Alleles ◽

Whole Genome Resequencing

Abstract Cultivated peanut (Arachis hypogaea L.) is rich in edible oil and protein, which is widely planted around the world as an oil and cash crop. However, aflatoxin contamination seriously affects the quality safety of peanut, hindering the development of peanut industry and threatening consumers’ health. Breeding peanut varieties with resistance to Aspergillus flavus infection is important for control the aflatoxin contamination, and understanding of the genetic basis of resistance is vital to its genetic enhancement. In this study, we report the QTL mapping of resistance to A. flavus infection of a well-known resistant variety J11. A recombination inbred line (RIL) population was constructed by crossing a susceptible variety Zhonghua 16 and J11. Through whole-genome resequencing, a genetic linkage map was constructed with 2,802 recombination bins and an average inter-bin distance of 0.58 cM. Combined with phenotypic data of infection index in four consecutive years, six novel resistant QTLs were identified and they explained 5.03-10.87% phenotypic variances. The favorable alleles of five QTLs were from J11 while that of one QTL were from Zhonghua 16. The pyramiding of these favorable alleles significantly improved the resistance to A. flavus infection. These results could contribute greatly to understanding of genetic basis of A. flavus resistance and could be meaningful in further resistance improvement in peanut.

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Molecular Genetics of Migraine Headaches: A Review

Cephalalgia ◽

10.1046/j.1468-2982.2000.00003.x ◽

2000 ◽

Vol 20 (1) ◽

pp. 3-14 ◽

Cited By ~ 69

Author(s):

P Montagna

Keyword(s):

Serotonin Receptors ◽

Genetic Linkage ◽

World Wide ◽

Genetic Basis ◽

Association Studies ◽

Familial Hemiplegic Migraine ◽

Success Story ◽

Hemiplegic Migraine ◽

Migraine Headaches ◽

Prothrombotic Risk Factors

Following the recent discovery of neural calcium channel mutations in familial hemiplegic migraine, genetic linkage and association studies have been performed world-wide in an effort to unveil the genetic basis of the more common types of migraine too. Mutations in neural calcium channels, rnitochondrial DNA, serotonin receptors and transporter, dopamine receptors and genetic prothrombotic risk factors have been especially investigated and are discussed here. No unambiguous conclusions have, however, been reached. FHM remains an isolated success story in the quest for the genetic basis of migraine.

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Understanding the Genetic Basis of C4 Kranz Anatomy with a View to Engineering C3 Crops

Annual Review of Genetics ◽

10.1146/annurev-genet-120417-031217 ◽

2018 ◽

Vol 52 (1) ◽

pp. 249-270 ◽

Cited By ~ 27

Author(s):

Olga V. Sedelnikova ◽

Thomas E. Hughes ◽

Jane A. Langdale

Keyword(s):

Genetic Basis ◽

Genetic Regulation ◽

Crop Productivity ◽

Research Field ◽

Leaf Cell ◽

Cell Type ◽

Kranz Anatomy ◽

Genetic Mechanisms ◽

Metabolic Reactions ◽

Type Specification

One of the most remarkable examples of convergent evolution is the transition from C3 to C4 photosynthesis, an event that occurred on over 60 independent occasions. The evolution of C4 is particularly noteworthy because of the complexity of the developmental and metabolic changes that took place. In most cases, compartmentalized metabolic reactions were facilitated by the development of a distinct leaf anatomy known as Kranz. C4 Kranz anatomy differs from ancestral C3 anatomy with respect to vein spacing patterns across the leaf, cell-type specification around veins, and cell-specific organelle function. Here we review our current understanding of how Kranz anatomy evolved and how it develops, with a focus on studies that are dissecting the underlying genetic mechanisms. This research field has gained prominence in recent years because understanding the genetic regulation of Kranz may enable the C3-to-C4 transition to be engineered, an endeavor that would significantly enhance crop productivity.

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Genetic Dissection of Haploid Male Fertility in Maize (Zea mays L.)

10.1101/318386 ◽

2018 ◽

Author(s):

Jiwei Yang ◽

Haochuan Li ◽

Yanzhi Qu ◽

Qiong Chen ◽

Jihua Tang ◽

...

Keyword(s):

Male Fertility ◽

Genetic Basis ◽

Mapping Population ◽

Transgressive Segregation ◽

Haploid Genome ◽

Genetic Dissection ◽

Genome Doubling ◽

Haploid Male ◽

Female Donor ◽

Simple Sequence

AbstractHaploid genome doubling is a key limiting step of haploid breeding in maize. Spontaneous restoration of haploid male fertility (HMF) provides a method by which costs can be saved and which does not require the use of toxic chemicals, in contrast to the artificial doubling process. To reveal the genetic basis of HMF, haploids were obtained from the offspring of 285 F2:3 families, derived from the cross Zheng58× K22. The F2:3 families were used as female donor and YHI-1 as the male inducer line. The rates of HMF from each family line were evaluated at two field sites over two planting seasons. Quantitative trait loci (QTL) for HMF were identified using a genetic linkage map containing 157 simple sequence repeat (SSR) markers. QTL for HMF displayed incomplete dominance. Transgressive segregation of haploids from F2:3 families was observed relative to haploids derived from the two parents of the mapping population. A total of nine QTL were detected, which were distributed on chromosomes 1, 3, 4, 7, and 8. Three QTL, qHMF3b, qHMF7a, and qHMF7b were detected in both locations, respectively. In our mapping population, HMF was controlled by three major QTL. These QTL could be useful to predict the ability of spontaneous haploid genome doubling in related breeding materials, and to accelerate the haploid breeding process by introgression or aggregation of those QTL.

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Gata4 Is Essential for Normal Testicular Development and Male Fertility.

Biology of Reproduction ◽

10.1093/biolreprod/85.s1.571 ◽

2011 ◽

Vol 85 (Suppl_1) ◽

pp. 571-571 ◽

Cited By ~ 2

Author(s):

Jiachen Li ◽

Huili Zheng ◽

Wei Yan

Keyword(s):

Male Fertility ◽

Testicular Development

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Hepatocarcinogenesis: A Polygenic Model of Inherited Predisposition to Cancer

Tumori Journal ◽

10.1177/030089169608200101 ◽

1996 ◽

Vol 82 (1) ◽

pp. 1-5 ◽

Cited By ~ 14

Author(s):

Tommaso A. Dragani ◽

Federico Canzian ◽

Giacomo Manenti ◽

Marco A. Pierotti

Keyword(s):

Genetic Linkage ◽

Genetic Basis ◽

Cell Kinetics ◽

Hepatocellular Cancer ◽

Strain Differences ◽

Polygenic Inheritance ◽

Inherited Predisposition ◽

Neoplastic Lesions ◽

C3h Mice ◽

Resistant Strains

The murine inbred strain C3H provides an experimental model of inherited predisposition to hepatocellular cancer. Hepatocellular neoplastic lesions induced by chemical carcinogens reach a volume 10-100-fold greater in C3H mice than in genetically resistant strains. However, the huge strain differences in tumor size are explained by relatively small differences (10%-30%) in tumor cell kinetics. Genetic linkage experiments in different crosses demonstrated that six unlinked hepatocarcinogen sensitivity ( Hcs) and two hepatocarcinogen resistance ( Hcr) loci determined quantitative variations in susceptibility to hepatocarcinogenesis. Such results provide the genetic basis for the strain variations in susceptibility to hepatocarcinogenesis and demonstrate a new model of polygenic inheritance of predisposition to cancer.

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Role of Selective Autophagy in Spermatogenesis and Male Fertility

Cells ◽

10.3390/cells9112523 ◽

2020 ◽

Vol 9 (11) ◽

pp. 2523

Author(s):

Chunyu Lv ◽

Xiaoli Wang ◽

Ying Guo ◽

Shuiqiao Yuan

Keyword(s):

Male Infertility ◽

Male Fertility ◽

Genetic Regulation ◽

Underlying Mechanism ◽

Intracellular Pathogens ◽

Selective Autophagy ◽

Reproductive Processes ◽

Infertile Patients ◽

Shed Light

Autophagy is a “self-eating” process that engulfs cellular contents for their subsequent digestion in lysosomes to engage the metabolic need in response to starvation or environmental insults. According to the contents of degradation, autophagy can be divided into bulk autophagy (non-selective autophagy) and selective autophagy. Bulk autophagy degrades non-specific cytoplasmic materials in response to nutrient starvation while selective autophagy targets specific cargoes, such as damaged organelles, protein aggregates, and intracellular pathogens. Selective autophagy has been documented to relate to the reproductive processes, especially for the spermatogenesis, fertilization, and biosynthesis of testosterone. Although selective autophagy is vital in the field of reproduction, its role and the underlying mechanism have remained unclear. In this review, we focus on selective autophagy to discuss the recent advances in our understanding of the mechanism and role of selective autophagy on spermatogenesis and male fertility in mammals. Understanding the role of selective autophagy during spermatogenesis will promote the recognition of genetic regulation in male infertility, and shed light on therapies of infertile patients.

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