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Blood Nov 2013
Topics: Female; Hemoglobin C Disease; Homozygote; Humans
PubMed: 24263962
DOI: 10.1182/blood-2013-09-526764 -
Journal of the American College of... Aug 2017
Topics: Child; Cholesterol, LDL; Homozygote; Humans; Hyperlipoproteinemia Type II; Mutation; Rosuvastatin Calcium
PubMed: 28838367
DOI: 10.1016/j.jacc.2017.06.057 -
Scientific Reports Feb 2023SAM domain-containing protein 1 (SAMD1) has been implicated in atherosclerosis, as well as in chromatin and transcriptional regulation, suggesting a versatile and...
SAM domain-containing protein 1 (SAMD1) has been implicated in atherosclerosis, as well as in chromatin and transcriptional regulation, suggesting a versatile and complex biological function. However, its role at an organismal level is currently unknown. Here, we generated SAMD1 and SAMD1 mice to explore the role of SAMD1 during mouse embryogenesis. Homozygous loss of SAMD1 was embryonic lethal, with no living animals seen after embryonic day 18.5. At embryonic day 14.5, organs were degrading and/or incompletely developed, and no functional blood vessels were observed, suggesting failed blood vessel maturation. Sparse red blood cells were scattered and pooled, primarily near the embryo surface. Some embryos had malformed heads and brains at embryonic day 15.5. In vitro, SAMD1 absence impaired neuronal differentiation processes. Heterozygous SAMD1 knockout mice underwent normal embryogenesis and were born alive. Postnatal genotyping showed a reduced ability of these mice to thrive, possibly due to altered steroidogenesis. In summary, the characterization of SAMD1 knockout mice suggests a critical role of SAMD1 during developmental processes in multiple organs and tissues.
Topics: Mice; Animals; Embryonic Development; Embryo, Mammalian; Mice, Knockout; Heterozygote; Homozygote
PubMed: 36810619
DOI: 10.1038/s41598-023-29779-3 -
British Medical Journal Feb 1970
Topics: Heterozygote; Homozygote; Humans; Molecular Biology; Thalassemia
PubMed: 5434668
DOI: 10.1136/bmj.1.5693.431-a -
British Journal of Cancer Dec 1969
Topics: Carcinogens; Cell Division; Chromosome Aberrations; Homozygote; Models, Biological; Mutagens; Oncogenic Viruses; Polyploidy
PubMed: 5367334
DOI: 10.1038/bjc.1969.92 -
Journal of Medical Genetics Aug 1997Auditory-pigmentary syndromes are caused by physical absence of melanocytes from the skin, hair, eyes, or the stria vascularis of the cochlea. Dominantly inherited... (Review)
Review
Auditory-pigmentary syndromes are caused by physical absence of melanocytes from the skin, hair, eyes, or the stria vascularis of the cochlea. Dominantly inherited examples with patchy depigmentation are usually labelled Waardenburg syndrome (WS). Type I WS, characterised by dystopia canthorum, is caused by loss of function mutations in the PAX3 gene. Type III WS (Klein-Waardenburg syndrome, with abnormalities of the arms) is an extreme presentation of type I; some but not all patients are homozygotes. Type IV WS (Shah-Waardenburg syndrome with Hirschsprung disease) can be caused by mutations in the genes for endothelin-3 or one of its receptors, EDNRB. Type II WS is a heterogeneous group, about 15% of whom are heterozygous for mutations in the MITF (microphthalmia associated transcription factor) gene. All these forms show marked variability even within families, and at present it is not possible to predict the severity, even when a mutation is detected. Characterising the genes is helping to unravel important developmental pathways in the neural crest and its derivatives.
Topics: Endothelin-3; Eye Color; Face; Female; Homozygote; Humans; Incidence; Male; Prevalence; Receptors, Endothelin; Waardenburg Syndrome
PubMed: 9279758
DOI: 10.1136/jmg.34.8.656 -
The Journal of Heredity Dec 2021Parthenogenesis is a relatively rare event in birds, documented in unfertilized eggs from columbid, galliform, and passerine females with no access to males. In the...
Parthenogenesis is a relatively rare event in birds, documented in unfertilized eggs from columbid, galliform, and passerine females with no access to males. In the critically endangered California condor, parentage analysis conducted utilizing polymorphic microsatellite loci has identified two instances of parthenogenetic development from the eggs of two females in the captive breeding program, each continuously housed with a reproductively capable male with whom they had produced offspring. Paternal genetic contribution to the two chicks was excluded. Both parthenotes possessed the expected male ZZ sex chromosomes and were homozygous for all evaluated markers inherited from their dams. These findings represent the first molecular marker-based identification of facultative parthenogenesis in an avian species, notably of females in regular contact with fertile males, and add to the phylogenetic breadth of vertebrate taxa documented to have reproduced via asexual reproduction.
Topics: Female; Fertility; Homozygote; Humans; Male; Parthenogenesis; Phylogeny
PubMed: 34718632
DOI: 10.1093/jhered/esab052 -
Genetics, Selection, Evolution : GSE Dec 2022The availability of genome-wide marker data allows estimation of inbreeding coefficients (F, the probability of identity-by-descent, IBD) and, in turn, estimation of the...
BACKGROUND
The availability of genome-wide marker data allows estimation of inbreeding coefficients (F, the probability of identity-by-descent, IBD) and, in turn, estimation of the rate of inbreeding depression (ΔID). We investigated, by computer simulations, the accuracy of the most popular estimators of inbreeding based on molecular markers when computing F and ΔID in populations under random mating, equalization of parental contributions, and artificially selected populations. We assessed estimators described by Li and Horvitz (F and F), VanRaden (F and F), Yang and colleagues (F and F), marker homozygosity (F), runs of homozygosity (F) and estimates based on pedigree (F) in comparison with estimates obtained from IBD measures (F).
RESULTS
If the allele frequencies of a base population taken as a reference for the computation of inbreeding are known, all estimators based on marker allele frequencies are highly correlated with F and provide accurate estimates of the mean ΔID. If base population allele frequencies are unknown and current frequencies are used in the estimations, the largest correlation with F is generally obtained by F and the best estimator of ΔID is F. The estimators F and F have the poorest performance in most scenarios. The assumption that base population allele frequencies are equal to 0.5 results in very biased estimates of the average inbreeding coefficient but they are highly correlated with F and give relatively good estimates of ΔID. Estimates obtained directly from marker homozygosity (F) substantially overestimated ΔID. Estimates based on runs of homozygosity (F) provide accurate estimates of inbreeding and ΔID. Finally, estimates based on pedigree (F) show a lower correlation with F than molecular estimators but provide rather accurate estimates of ΔID. An analysis of data from a pig population supports the main findings of the simulations.
CONCLUSIONS
When base population allele frequencies are known, all marker-allele frequency-based estimators of inbreeding coefficients generally show a high correlation with F and provide good estimates of ΔID. When base population allele frequencies are unknown, F is the marker frequency-based estimator that is most correlated with F, and F provides the most accurate estimates of ΔID. Estimates from F are also very precise in most scenarios. The estimators F and F have the poorest performances.
Topics: Swine; Animals; Inbreeding; Inbreeding Depression; Polymorphism, Single Nucleotide; Homozygote; Pedigree; Inflammatory Bowel Diseases; Genotype
PubMed: 36575379
DOI: 10.1186/s12711-022-00772-0 -
Acta Medica Iranica Nov 2017Several studies have evaluated the association between interleukin-6 (IL-6) -174 G/C polymorphism and Graves' disease (GD); however, the results have been inconsistent.... (Meta-Analysis)
Meta-Analysis Review
Several studies have evaluated the association between interleukin-6 (IL-6) -174 G/C polymorphism and Graves' disease (GD); however, the results have been inconsistent. In the current study, a meta-analysis was performed to assess the association of IL6 -174 G/C polymorphism with Graves' disease. Medline, EMBASE, and Web of Science databases were searched to identify all eligible studies published before August 2016. Odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were calculated to assess the strength of association in dominant, recessive, allelic, homozygotes contrast, and heterozygotes contrast models. A total of four case-control studies with 554 GD cases and 1201 healthy controls were included in this meta-analysis. In the combined analysis, the results showed significant association between the IL6 -174 G/C polymorphism and the risk for GD in dominant model (OR=1.39, 95% CI: 1.07-1.80), recessive model (OR=2.75, 95% CI: 1.01-7.55) and homozygote contrast model (OR=3.25, 95% CI: 1.1-9.58). No publication bias was found in the current study (all P>0.05). The meta-analysis results suggested that the IL6 -174 G/C polymorphism was indicated to be associated with the risk of GD. Further studies are warranted to confirm these results.
Topics: Alleles; Genetic Predisposition to Disease; Graves Disease; Heterozygote; Homozygote; Humans; Interleukin-6; Odds Ratio; Polymorphism, Single Nucleotide; Risk Factors
PubMed: 29307154
DOI: No ID Found -
Nature Communications Jun 2023The benefits of large-scale genetic studies for healthcare of the populations studied are well documented, but these genetic studies have traditionally ignored people...
The benefits of large-scale genetic studies for healthcare of the populations studied are well documented, but these genetic studies have traditionally ignored people from some parts of the world, such as South Asia. Here we describe whole genome sequence (WGS) data from 4806 individuals recruited from the healthcare delivery systems of Pakistan, India and Bangladesh, combined with WGS from 927 individuals from isolated South Asian populations. We characterize population structure in South Asia and describe a genotyping array (SARGAM) and imputation reference panel that are optimized for South Asian genomes. We find evidence for high rates of reproductive isolation, endogamy and consanguinity that vary across the subcontinent and that lead to levels of rare homozygotes that reach 100 times that seen in outbred populations. Founder effects increase the power to associate functional variants with disease processes and make South Asia a uniquely powerful place for population-scale genetic studies.
Topics: Humans; Asian People; Bangladesh; Founder Effect; Homozygote; India; Pakistan; South Asian People
PubMed: 37291107
DOI: 10.1038/s41467-023-38766-1