scholarly journals A Frameshift Mutation in MC1R and a High Frequency of Somatic Reversions Cause Black Spotting in Pigs

Genetics ◽  
2001 ◽  
Vol 158 (2) ◽  
pp. 779-785 ◽  
Author(s):  
J M H Kijas ◽  
M Moller ◽  
G Plastow ◽  
L Andersson

Abstract Black spotting on a red or white background in pigs is determined by the EP allele at the MC1R/Extension locus. A previous comparison of partial MC1R sequences revealed that EP shares a missense mutation (D121N) with the ED2 allele for dominant black color. Sequence analysis of the entire coding region now reveals a second mutation in the form of a 2-bp insertion at codon 23 (nt67insCC). This mutation expands a tract of six C nucleotides to eight and introduces a premature stop codon at position 56. This frameshift mutation is expected to cause a recessive red color, which was in fact observed in some breeds with the EP allele present (Tamworth and Hereford). RT-PCR analyses were conducted using skin samples taken from both spotted and background areas of spotted pigs. The background red area had transcript only from the mutant nt67insCC MC1R allele, whereas the black spot also contained a transcript without the 2-bp insertion. This indicates that black spots are due to somatic reversion events that restore the frame and MC1R function. The phenotypic expression of the EP allele is highly variable and the associated coat color ranges from red, red with black spots, white with black spots, to almost completely solid black. In several breeds of pigs the phenotypic manifestation of this allele has been modified by selection for or against black spots.

2019 ◽  
Vol 32 (8) ◽  
pp. 752-758
Author(s):  
Peng Fan ◽  
Yu-Mo Zhao ◽  
Di Zhang ◽  
Ying Liao ◽  
Kun-Qi Yang ◽  
...  

Abstract BACKGROUND Liddle syndrome (LS) is an autosomal dominant disorder caused by single-gene mutations of the epithelial sodium channel (ENaC). It is characterized by early-onset hypertension, spontaneous hypokalemia and low plasma renin and aldosterone concentrations. In this study, we reported an LS pedigree with normokalemia resulting from a novel SCNN1G frameshift mutation. METHODS Peripheral blood samples were collected from the proband and eight family members for DNA extraction. Next-generation sequencing and Sanger sequencing were performed to identify the SCNN1G mutation. Clinical examinations were used to comprehensively evaluate the phenotypes of two patients. RESULTS Genetic analysis identified a novel SCNN1G frameshift mutation, p.Arg586Valfs*598, in the proband with LS. This heterozygous frameshift mutation generated a premature stop codon and deleted the vital PY motif of ENaC. The same mutation was present in his elder brother with LS, and his mother without any LS symptoms. Biochemical examination showed normokalemia in the three mutation carriers. The mutation identified was not found in any other family members, 100 hypertensives, or 100 healthy controls. CONCLUSIONS Our study identified a novel SCNN1G frameshift mutation in a Chinese family with LS, expanding the genetic spectrum of SCNN1G. Genetic testing helped us identify LS with a pathogenic mutation when the genotypes and phenotype were not completely consistent because of the hypokalemia. This case emphasizes that once a proband is diagnosed with LS by genetic testing, family genetic sequencing is necessary for early diagnosis and intervention for other family members, to protect against severe cardiovascular complications.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1136-1136
Author(s):  
Tarek Owaidah ◽  
Hala Abalkhail ◽  
Abdulrahman Al Musa ◽  
Hasan Mosmali ◽  
Albanyan Abdulmajeed ◽  
...  

Abstract Abstract 1136 Introduction: Glanzmann thrombasthenia (GT) is a rare autosomal recessive inherited bleeding disorder characterized by an impaired platelet aggregation and variable bleeding tendency. Inherited genetic mutations in integrin alpha IIb and beta3 (ITGA2B, ITGB3) result in a heterogeneity of the thrombasthenia phenotypes. It is phenotypically expressed in homozygotes or compound heterozygotes, given that 50% of normal aIIbb3 is sufficient to guarantee unimpaired platelet function that result in asymptomatic carriers. Defects in ITGB3 result in failure of binding of B3 and alpha IIb. These defects had been reported in Arabs (Iraqi Jews). We are reporting some results of Saudi GT genotype project. Materials & Methods: In this study, we analyzed the entire coding region ITGB3 gene using polymerase chain reaction (PCR) and direct sequencing with primers specifically designed to amplify the coding region of exon 1–15 and exon /Intron boundaries in a cohort of 51 GT patients diagnosed and treated in our institute. Results: Out of 51 cases from 20 families had mutational screening of the ITGB3 gene with the aim to detect the causative pathogenic mutations to enable the pre-symptomatic diagnosis in at risk family members. In this study we detect 1 novel germline mutation c.2190delC (p.Ser703fs) in exon 13. The mutation is predicted to result in premature stop codon and protein truncation. The mutation was detected in 6 patients in homozygous stat (3 males and 3 females). Three tested samples from the patients family members detected the mutation in heterozygous state and all of them were asymptomatic with normal PFA and Intact expression of Platelet Glycoprotiens CD41(Gpllb), CD42a(GPIX), CD42b(GPlb), and CD61(Gpllla). All the GT patients with this mutation were type I GT with Prolonged PFA and complete absence of CD41(Gpllb) and CD61(Gpllla) glycoprotein. Conclusion: The result of this study represents the first Molecular analysis of ITGB3 gene in Saudi Arabia and displays the existence of novel pathogenic and possibly a founder effect in Saudi families. Disclosures: No relevant conflicts of interest to declare.


Hemorrhoids and varicose veins are conditions resulting from loss of vascular integrity and, despite being worldwide health concerns, their pathogenesis has not been clearly defined. Many risk factors have been linked to the development of these complications including diet, defecating habits, alcohol consumption and other physiological factors. There are limited studies involving the possible role of genetic mutations in the development of hemorrhoids and varicose veins. FoxC2 is an important transcription factor that plays many roles in a variety of embryonic developmental processes, including angiogenesis. In the current study, we aimed to investigate the role of the FOXC2 gene variations in the development of familial hemorrhoids and varicose veins in the Jordanian population. Thirty-two samples were collected from eight families manifested hemorrhoids and/or varicose veins conditions. DNA sequencing was performed to screen variation in the FOXC2 gene. Two individuals with severe and early onset of hemorrhoids and varicose veins from the same family showed a frameshift mutation (881'inT) in the coding exon of the FOXC2 gene resulting in a premature stop codon at position +1386 (294 residues truncated peptide). In conclusion, our results support a possible role of genetic predisposition in the development of hemorrhoids and varicose veins with a frequency of 6% in the selected population


1995 ◽  
Vol 74 (06) ◽  
pp. 1411-1415 ◽  
Author(s):  
Masaaki Noda ◽  
Kingo Fujimura ◽  
Toshiro Takafuta ◽  
Takeshi Shimomura ◽  
Tetsuro Fujlmoto ◽  
...  

SummaryBernard-Soulier syndrome (BSS) is a rare inherited bleeding disorder, which is caused by deficiency or decrease of the platelet GPIb/IX/V complex. Analysis of two patients with BSS by How cytometry of the blood revealed different expression patterns of the components of the GPIb/IX/V complex. In case 1, GPIX was completely absent but residual amounts of GPIbα and GPV were detectable; in case 2, GPIbα was completely absent. We amplified the coding regions of GPIbα, GPIbß, GPV, and GPIX from the patients’ genomic DNA with the polymerase chain reaction (PCR) and sequenced the PCR products. In case 1, we identified a point mutation in the GPIX coding region that changes the codon for tryptophan-126 (TGG) to a nonsense codon (TGA). In case 2, we found a deletion of nucleotide within seven adenine repeats at the position of 1932 to 1938 in the coding region of GPIbα, which causes a frame shift that results in 58 altered amino acids and a premature stop codon. These genetic changes alter the transmembrane domain of GPIX or GPIbα and, therefore, would prevent proper insertion of the proteins in the plasma membrane. Thus, abnormality of a single component protein (GPIX or GPIbα) alters the assembly of the GPIb/IX/V complex and causes heterogenous surface expression of GPIbα, GPV and GPIX.


2001 ◽  
Vol 86 (9) ◽  
pp. 4068-4071 ◽  
Author(s):  
Sorahia Domenice ◽  
Ana Claudia Latronico ◽  
Vinicius Nahime Brito ◽  
Ivo Jorge Prado Arnhold ◽  
Fernando Kok ◽  
...  

Primary adrenal insufficiency is a rare condition in pediatric age, and its association with precocious sexual development is very uncommon. We report a 2-yr-old Brazilian boy with DAX1 gene mutation whose first clinical manifestation was isosexual gonadotropin-independent precocious puberty. He presented with pubic hair, enlarged penis and testes, and advanced bone age. T levels were elevated, whereas basal and GnRH-stimulated LH levels were compatible with a prepubertal pattern. Chronic GnRH agonist therapy did not reduce T levels, supporting the diagnosis of gonadotropin-independent precocious puberty. Testotoxicosis was ruled out after normal sequencing of exon 11 of the LH receptor gene. At age 3 yr he developed clinical and hormonal features of severe primary adrenal insufficiency. The entire coding region of the DAX1 gene was analyzed through direct sequencing. A nucleotide G insertion between nucleotides 430 and 431 in exon 1, resulting in a novel frameshift mutation and a premature stop codon at position 71 of DAX-1, was identified. Surprisingly, steroid replacement therapy induced a clear decrease in testicular size and T levels to the prepubertal range. These findings suggest that chronic excessive ACTH levels resulting from adrenal insufficiency may stimulate Leydig cells and lead to gonadotropin-independent precocious puberty in some boys with DAX1 gene mutations.


Genes ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 639
Author(s):  
Samantha L. Van Buren ◽  
Katie M. Minor ◽  
Robert A. Grahn ◽  
James R. Mickelson ◽  
Jennifer C. Grahn ◽  
...  

Altered melanosome transport in melanocytes, resulting from variants in the melanophilin (MLPH) gene, are associated with inherited forms of coat color dilution in many species. In dogs, the MLPH gene corresponds to the D locus and two variants, c.−22G > A (d1) and c.705G > C (d2), leading to the dilution of coat color, as described. Here, we describe the independent investigations of dogs whose coat color dilution could not be explained by known variants, and who report a third MLPH variant, (c.667_668insC) (d3), which leads to a frameshift and premature stop codon (p.His223Profs*41). The d3 allele is found at low frequency in multiple dog breeds, as well as in wolves, wolf-dog hybrids, and indigenous dogs. Canids in which the d3 allele contributed to the grey (dilute) phenotype were d1/d3 compound heterozygotes or d3 homozygotes, and all non-dilute related dogs had one or two D alleles, consistent with a recessive inheritance. Similar to other loci responsible for coat colors in dogs, this, alongside likely additional allelic heterogeneity at the D locus, or other loci, must be considered when performing and interpreting genetic testing.


2018 ◽  
Vol 71 (9) ◽  
pp. 821-824 ◽  
Author(s):  
Nasrollah Saleh-Gohari ◽  
Kolsoum Saeidi ◽  
Roya Zeighaminejad

AimsFucosidosis is a rare autosomal recessive lysosomal storage disorder caused by α-L-fucosidase deficiency as a result of FUCA1 gene mutations. Here, we studied clinical features and the molecular basis of fucosidosis in a family from Iran, including two probands and nine family members.MethodsDNA sample of two probands were screened for gene defects using a next generation sequencing technique. The sequencing processes were performed on an Illumina Hiseq 4000 platform. Sequence reads were analysed using BWA-GATK.ResultsNext generation sequencing revealed a frameshift mutation caused by 2 bp deletion (c.837_838 delTG; p.Cys279) in the FUCA1 gene. The identified mutation was tested in all participants. Homozygous patients had almost all the complications associated with fucosidosis, while heterozygous carriers were unaffected.ConclusionsThe variant c.837_838 delTG; p.Cys279 has not been reported previously and is predicted to be pathogenic due to a premature stop codon.


1999 ◽  
Vol 84 (5) ◽  
pp. 1751-1753 ◽  
Author(s):  
Brigitta Thiele ◽  
Wolfgang Weidemann ◽  
Doris Schnabel ◽  
Gabriela Romalo ◽  
Hans-Udo Schweikert ◽  
...  

We describe a novel mutation in exon 1 of the androgen receptor gene in a patient with complete androgen insensitivity (CAIS). Endocrine findings were typical for androgen insensitivity (testosterone serum levels in the upper limit of normal males and increased LH serum concentrations). Biochemical investigations in cultured genital skin fibroblasts of the patient showed a normal 5α-reductase activity but a complete absence of androgen binding. Western blot analysis revealed no detectable protein product. Sequence analysis of the entire coding region of the androgen receptor gene resulted in the identification of a 2-bp deletion in codon 472, causing frameshift and introduction of a premature stop codon 27 codons downstream of the mutation.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3691 ◽  
Author(s):  
Yao Lin ◽  
Wei Yin ◽  
Zhuan Bian

Background The phenotypic characters of X -linked Hypohidrotic Ectodermal Dysplasia (XLHED) are the dysplasia of epithelial- and mesenchymal-derived organs. Ectodysplasin (EDA) is the causative gene of XLHED. Methods The current study reported a large Chinese XLHED pedigree. The genomic DNA of adult and fetus was extracted from peripheral blood and shed chorion cell respectively. The nucleotide variation in EDA gene was screened through direct sequencing the coding sequence. The methylation state of EDA gene’s promoter was evaluated by pyrosequencing. Results This Chinese XLHED family had two male patients and three carriers. All of them were with a novel EDA frameshift mutation. The mutation, c.172-173insGG, which leads to an immediate premature stop codon in exon one caused severe structural changes of EDA. Prenatal diagnosis suggested that the fetus was a female carrier. The follow-up observation of this child indicated that she had mild hypodontia of deciduous teeth at age six. The methylation level of EDA gene’s promoter was not related to carriers’ phenotype changes in this family. Discussion We reported a new frameshift mutation of EDA gene in a Chinese family. Prenatal diagnosis can help to predict the disease status of the fetus.


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