1.Analysis of FMR1 gene CGG repeats among patients with diminished ovarian reserve.
Wenbin HE ; Weilin TANG ; Yi LIAO ; Wen LI ; Fei GONG ; Guangxiu LU ; Ge LIN ; Juan DU ; Yueqiu TAN
Chinese Journal of Medical Genetics 2021;38(4):343-346
OBJECTIVE:
To explore the correlation between Fragile X mental retardation gene-1 (FMR1) gene CGG repeats with diminished ovarian reserve (DOR).
METHODS:
For 214 females diagnosed with DOR, DNA was extracted from peripheral blood samples. FMR1 gene CGG repeats were determined by PCR and capillary electrophoresis.
RESULTS:
Three DOR patients were found to carry FMR1 premutations, and one patient was found to carry gray zone FMR1 repeats. After genetic counseling, one patient and the sister of another patient, both carrying FMR1 permutations, conceived naturally. Prenatal diagnosis showed that both fetuses have carried FMR1 permutations.
CONCLUSION
FMR1 gene permutation may be associated with DOR. Determination of FMR1 gene CGG repeats in DOR patients can provide a basis for genetic counseling and guidance for reproduction.
Female
;
Fragile X Mental Retardation Protein/metabolism*
;
Fragile X Syndrome/genetics*
;
Humans
;
Ovarian Diseases
;
Ovarian Reserve/genetics*
;
Primary Ovarian Insufficiency/genetics*
;
Trinucleotide Repeats/genetics*
2.Significance and case analysis of FMR1 mutation screening during early and middle pregnancy.
Qinying CAO ; Weihong MU ; Donglan SUN ; Junzhen ZHU ; Jun GE ; Yuanyuan PENG ; Jing ZHANG
Chinese Journal of Medical Genetics 2021;38(5):450-453
OBJECTIVE:
To screen for mutations of fragile X mental retardation 1 (FMR1) gene during early and middle pregnancy and provide prenatal diagnosis for those carrying high-risk CGG trinucleotide expansions.
METHODS:
Peripheral blood samples of 2316 pregnant women at 12 to 21(+6) gestational weeks were collected for the extraction of genomic DNA. CGG repeats of the FMR1 gene were detected by fluorescence PCR and capillary electrophoresis. Genetic counseling and prenatal diagnosis were provided for 3 women carrying the premutations.
RESULTS:
The carrier rate of CGG repeats of the FMR1 gene was 1 in 178 for the intermediate type and 1 in 772 for the premutation types. The highest frequency allele of CGG was 29 repeats, which accounted for 49.29%, followed by 30 repeats (28.56%) and 36 repeats (8.83%). In case 1, the fetus had a karyotype of 45,X, in addition with premutation type of CGG expansion of the FMR1 gene. Following genetic counseling, the couple chose to terminate the pregnancy through induced labor. The numbers of CGG repeats were respectively 70/- and 29/30 for the husband and wife. In case 2, amniocentesis was performed at 20 weeks of gestation. The number of CGG repeats of the FMR1 gene was 29/-. No abnormality was found in the fetal karyotype and chromosomal copy number variations. The couple chose to continue with the pregnancy. Case 3 refused prenatal diagnosis after genetic counseling and gave birth to a girl at full term, who had a birth weight of 2440 g and no obvious abnormality found during follow-up.
CONCLUSION
Pregnant women should be screened for FMR1 gene mutations during early and middle pregnancy, and those with high-risk CGG expansions should undergo prenatal diagnosis, genetic counseling and family study.
DNA Copy Number Variations
;
Female
;
Fragile X Mental Retardation Protein/genetics*
;
Fragile X Syndrome/genetics*
;
Genetic Counseling
;
Humans
;
Mutation
;
Pregnancy
;
Trinucleotide Repeat Expansion
;
Trinucleotide Repeats
3.Detection and analysis of dynamic variant in a pedigree affected with spinocerebellar ataxia type 3.
Chen CHEN ; Xuechao ZHAO ; Xiangdong KONG
Chinese Journal of Medical Genetics 2020;37(12):1364-1367
OBJECTIVE:
To analyze the dynamic variant and clinical subtype of a pedigree affected with spinocerebellar ataxia (SCA) by using fluorescent-labeled primer combined with capillary electrophoresis.
METHODS:
Genomic DNA was extracted from 8 members including 6 patients and 2 healthy individuals from the pedigree. Six pairs of fluorescent-labeled primers were designed to screen pathological variants in association with common subtypes of SCA including SCA1, SCA2, SCA3, SCA6, SCA12 and SCA17.The PCR products were detected by capillary electrophoresis.
RESULTS:
The number of CAG repeats in the SCA3 gene of the proband were determined as 8 and 70, exceeded the normal range(12 to 40), which suggested a diagnosis of SCA3. The other five patients were all detected with abnormal CAG repeats in the SCA3 gene, while the two healthy individuals were determined to be within the normal range.
CONCLUSION
The abnormal expansion of CAG repeats in the SCA3 gene probably underlay the pathogenesis of the disease in this pedigree. Combined fluorescent-labeled primers PCR and capillary electrophoresis can detect dynamic variants among SCA patients with efficiency and accuracy.
Ataxin-3/genetics*
;
Genetic Variation
;
Humans
;
Machado-Joseph Disease/genetics*
;
Pedigree
;
Repressor Proteins/genetics*
;
Trinucleotide Repeats/genetics*
4.Positive Correlation between Androgen Receptor CAG Repeat Length and Metabolic Syndrome in a Korean Male Population
Jong Wook KIM ; Young Dae BAE ; Sun Tae AHN ; Jin Wook KIM ; Je Jong KIM ; Du Geon MOON
The World Journal of Men's Health 2018;36(1):73-78
PURPOSE: In epidemiological studies, there are various associations of androgen receptor (AR) CAG with several diseases or phenotypes. However, the relationship between CAG repeat length and metabolic syndrome (MS) remains unclear, especially in Asian populations. This study was designed to evaluate the relationship between AR CAG repeat length polymorphism and MS in a Korean male population. MATERIALS AND METHODS: We explored the relationship between AR CAG repeat length polymorphism and MS in a Korean male population (n=337) from 2013 to 2014. AR CAG repeat were determined by microsatellite fragment sizing. Components of MS and laboratory data (lipid profile, fasting glucose, and glycated hemoglobin (HbA1c)) were analyzed with AR CAG repeat length. RESULTS: The mean AR CAG repeat length was 22.3±4.7. Sixty-nine men (20.5%) were diagnosed with MS. Men with MS showed significantly longer AR CAG repeat lengths compared with men without MS (26.2 vs. 21.4, p < 0.001). With increasing CAG repeat, the number of components meeting the NCEP criteria increased significantly. AR CAG repeat length was associated significantly with high density lipoprotein (HDL), triglyceride, and HbA1c levels. In the multivariate analysis, CAG repeat length, waist circumference, and levels of HDL were independently associated with MS. (odds ratio (OR)=1.37, 1.19 and 0.90, p < 0.001, 0.045, and 0.001, respectively). CONCLUSIONS: AR CAG repeat length was associated with MS and laboratory test results, such as those for HDL, triglycerides, and HbA1c, in Korean males. Longer CAG repeat length was identified as a risk factor for MS in Korean males.
Asian Continental Ancestry Group
;
Epidemiologic Studies
;
Fasting
;
Glucose
;
Hemoglobin A, Glycosylated
;
Humans
;
Lipoproteins
;
Male
;
Microsatellite Repeats
;
Multivariate Analysis
;
Phenotype
;
Receptors, Androgen
;
Risk Factors
;
Triglycerides
;
Trinucleotide Repeats
;
Waist Circumference
6.Clinical and genetic characteristics of patients with dentatorubro-pallidoluysian atrophy.
Hua LI ; Xiangshu HU ; Lingxia FEI ; Peiqi ZHANG ; Xinhao CHEN ; Mei OUYANG ; Wei ZHANG ; Xingzhou LIU
Chinese Journal of Medical Genetics 2016;33(5):610-614
OBJECTIVETo explore the clinical and genetic characteristics of patients with dentatorubro-pallidoluysian atrophy (DRPLA).
METHODSDNA analysis for DRPLA gene was performed in two patients. Clinical features and genetic testing of Chinese DRPLA patients reported in the literature were reviewed in terms of initial symptoms, CAG repeat and age of onset.
RESULTSBoth families were confirmed by genetic analysis. In family 1, the number of CAG repeat in the proband, his brother and his mother was determined respectively as 8/65, 8/53 and 8/18. In family 2, the number of CAG repeat was respectively 13/63, 13/18, 18/52 and 13/13 in the proband, his brother, his father and his mother. The size of the expanded CAG repeats has inversely correlated with the age at onset (P<0.05, r=- 0.555). The age at onset of epilepsy was 10 and that for the onset of ataxia is forty years in initial symptom.
CONCLUSIONThe clinical characteristics of DRPLA include epilepsy, ataxia and cognitive impairment. The initial symptoms are epilepsy in adolescence and ataxia in adults. The size of expanded CAG repeats inversely correlates with the age at onset. The initial symptoms are different with different age of onset. It is difficult to diagnose DRPLA at an early stage.
Adolescent ; Adult ; Aged ; Atrophy ; genetics ; Basal Ganglia Diseases ; diagnosis ; genetics ; DNA Mutational Analysis ; Dentate Gyrus ; pathology ; Family Health ; Female ; Globus Pallidus ; pathology ; Humans ; Male ; Middle Aged ; Nerve Tissue Proteins ; genetics ; Pedigree ; Trinucleotide Repeat Expansion ; genetics ; Young Adult
7.Analysis of CGG repeat instability in germline cells from two male fetuses affected with fragile X syndrome.
Ranhui DUAN ; Shiyu LUO ; Wen HUANG ; Haoxian LI ; Ying PENG ; Qian DU ; Lingqian WU
Chinese Journal of Medical Genetics 2016;33(5):606-609
OBJECTIVETo study the pattern of CGG repeat instability within germline cells derived from two male fetuses affected with Fragile X syndrome (FXS).
METHODSThe length and methylation status of CGG repeats within the testes of a fetus carrying a full FXS mutation and another fetus carrying mosaicism FXS mutation were analyzed with Southern blotting and AmplideX FMR1 PCR. Immunohistochemistry was also applied for the measurement of FMR1 protein (FMRP) expression within the testes.
RESULTSFor the fetus carrying the full mutation, Southern blotting analysis of the PCR product has detected an expected band representing the full mutation in its brain and a premutation band of > 160 CGG repeats in its testis. Whereas the pattern of premutation/full mutation in mosaic testis was similar to that in peripheral blood and no sign of contracted fragment was found other than a band of about 160 CGG repeats. Immunohistochemistry assay with a FMRP-specific antibody demonstrated a number of FMRP-positive germ cells, which suggested a contraction from full mutation to premutation alleles.
CONCLUSIONThis study has clarified the instability pattern of CGG repeat and expression of FMRP protein within the testes of fetuses affected with FXS, confirming that the CGG repeat can contract progressively within the germline. The FMRP expression in the testis is consistent with spermatogonium proliferation, and thus the contraction from full mutation to unmethylated premutations may occur for the requirement of FMRP expression during spermatogenesis. The better understanding of FMRP function during germ cell proliferation may elucidate the mechanism underlying the contraction of full FXS mutation in male germline.
Abortion, Eugenic ; Blotting, Southern ; Brain ; embryology ; metabolism ; DNA Methylation ; Fatal Outcome ; Fetus ; cytology ; metabolism ; Fragile X Mental Retardation Protein ; genetics ; metabolism ; Fragile X Syndrome ; diagnosis ; genetics ; Humans ; Immunohistochemistry ; Male ; Mosaicism ; Mutation ; Polymerase Chain Reaction ; Spermatozoa ; metabolism ; Testis ; cytology ; embryology ; metabolism ; Trinucleotide Repeat Expansion ; genetics
8.Carrier screening for (CGG)n repeat expansion of FMR1 gene in Korean women.
Kyung Min KANG ; Se Ra SUNG ; Ji Eun PARK ; Yun Jeong SHIN ; Sang Hee PARK ; Mi Uk CHIN ; Sang Woo LYU ; Dong Hyun CHA ; Sung Han SHIM
Journal of Genetic Medicine 2016;13(1):14-19
PURPOSE: We examined the prevalence and CGG/AGG repeat structure of expanded alleles of the FMR1 gene in preconceptional and pregnant Korean women. MATERIALS AND METHODS: The CGG repeats in the FMR1 genes of 1,408 women were analyzed by polymerase chain reaction and Southern blot analysis. To estimate the prevalence of expansion alleles, the individuals were divided into low risk and high risk group. RESULTS: Within this population, 98.4% had normal alleles and 1.6% had abnormal alleles including intermediate (0.6%), premutation (0.5%), full mutation (0.1%), and hemizygous (0.4%) alleles. There were 2 premutation alleles (1:666, 95% confidence interval [CI] 1:250-1,776) in the low risk group and 5 premutation alleles (1:15, 95% 1:6-36) in the high risk group. There were 8 intermediate alleles (1:167, 95% CI 1:130-213) in the low risk group and 1 intermediate alleles (1:76, 95% CI 1:11-533) in the high group. Six of the 7 premutation alleles did not contain AGG interruptions within the repeats and 1 had a single AGG interruption. Four of the 9 intermediate alleles contained 2-3 AGG, 4 had a single AGG, and 1 had no AGG interruptions. CONCLUSION: Our study demonstrates the prevalence and CGG/AGG structure of expansion alleles in Korean women. The identified premutation prevalence is higher than that of other Asian populations and lower than that of Caucasian populations. Although our study is limited by size and population bias, our findings could prove useful for genetic counseling of preconceptional or pregnant women.
Alleles
;
Asian Continental Ancestry Group
;
Bias (Epidemiology)
;
Blotting, Southern
;
Carrier State
;
Female
;
Fragile X Syndrome
;
Gene Frequency
;
Genetic Counseling
;
Humans
;
Mass Screening*
;
Polymerase Chain Reaction
;
Pregnant Women
;
Prevalence
;
Trinucleotide Repeat Expansion
9.No Association between (AAT)n Repeat Polymorphisms in the Cannabinoid Receptor 1 Gene and Smooth Pursuit Eye Movement Abnormality in Korean Patients with Schizophrenia.
Min Jae KIM ; Chae Ri KIM ; Jin Wan PARK ; Doo Hyun PAK ; Hyoung Doo SHIN ; Ihn Geun CHOI ; Sang Woo HAHN ; Jaeuk HWANG ; Yeon Jung LEE ; Sung Il WOO
Journal of the Korean Society of Biological Psychiatry 2016;23(4):148-156
OBJECTIVES: According to previous studies, the cannabinoid receptor 1 (CNR1) gene could be an important candidate gene for schizophrenia. Some studies have linked the (AAT)n trinucleotide repeat polymorphism in CNR1 gene with the risk of schizophrenia. Meanwhile, smooth pursuit eye movement (SPEM) has been regarded as one of the most consistent endophenotypes of schizophrenia. In this study, we investigated the association between the (AAT)n trinucleotide repeats in CNR1 gene and SPEM abnormality in Korean patients with schizophrenia. METHODS: We measured SPEM function in 167 Korean patients with schizophrenia (84 male, 83 female) and they were divided according to SPEM function into two groups, good and poor SPEM function groups. We also investigated allele frequencies of (AAT)n repeat polymorphisms on CNR1 gene in each group. A logistic regression analysis was performed to find the association between SPEM abnormality and the number of (AAT)n trinucleotide repeats. RESULTS: The natural logarithm value of signal/noise ratio (Ln S/N ratio) of the good SPEM function group was 4.34 ± 0.29 and that of the poor SPEM function group was 3.21 ± 0.70. In total, 7 types of trinucleotide repeats were identified, each containing 7, 10, 11, 12, 13, 14, and 15 repeats, respectively. In the patients with (AAT)₇ allele, the distributions of the good and poor SPEM function groups were 18 (11.1%) and 19 (11.0%) respectively. In the patients with (AAT)₁₀ allele, (AAT)₁₁ allele, (AAT)₁₂ allele, (AAT)₁₃ allele, (AAT)₁₄ allele and (AAT)₁₅ allele, the distributions of good and poor SPEM function groups were 13 (8.0%) and 12 (7.0%), 4 (2.5%) and 6 (3.5%), 31 (19.8%) and 35 (20.3%), 51 (31.5%) and 51 (29.7%), 36 (22.2%) and 45 (26.2%), 9 (5.6%) and 4 (2.3%) respectively. As the number of (AAT) n repeat increased, there was no aggravation of abnormality of SPEM function. CONCLUSIONS: There was no significant aggravation of SPEM abnormality along with the increase of number of (AAT)n trinucleotide repeats in the CNR1 gene in Korean patients with schizophrenia.
Alleles
;
Endophenotypes
;
Eye Movements*
;
Gene Frequency
;
Humans
;
Logistic Models
;
Male
;
Pursuit, Smooth*
;
Receptors, Cannabinoid*
;
Schizophrenia*
;
Trinucleotide Repeats
10.Clinical Characteristics and Genotype-Phenotype Correlation of Korean Patients with Spinal and Bulbar Muscular Atrophy.
Ju Sun SONG ; Kyung Ah KIM ; Ju Hong MIN ; Chang Seok KI ; Jong Won KIM ; Duk Hyun SUNG ; Byoung Joon KIM
Yonsei Medical Journal 2015;56(4):993-997
PURPOSE: Spinal and bulbar muscular atrophy (SBMA) is an X-linked motor neuron disease characterized by proximal muscle weakness, muscle atrophy, and fasciculation. Although SBMA is not uncommon in Korea, there is only one study reporting clinical characteristics and genotype-phenotype correlation in Korean patients. MATERIALS AND METHODS: In this study, age at the onset of symptoms, the score of severity assessed by impairment of activities of daily living milestones, and rate of disease progression, and their correlations with the number of CAG repeats in the androgen receptor (AR) gene, as well as possible correlations among clinical characteristics, were analyzed in 40 SBMA patients. RESULTS: The median ages at onset and at diagnosis were 44.5 and 52.5 years, respectively, and median interval between onset and diagnosis and median rate of disease progression were 5.0 years and 0.23 score/year, respectively. The median number of CAG repeats in the AR gene was 44 and the number of CAG repeats showed a significant inverse correlation with the age at onset of symptoms (r=-0.407, p=0.009). In addition, patients with early symptom onset had slower rate of disease progression. CONCLUSION: As a report with the largest and recent Korean cohort, this study demonstrates clinical features of Korean patients with SBMA and reaffirms the inverse correlation between the age at disease onset and the number of CAG repeats. Interestingly, this study shows a possibility that the rate of disease progression may be influenced by the age at onset of symptoms.
Activities of Daily Living
;
Adult
;
Age of Onset
;
Asian Continental Ancestry Group/*genetics
;
Bulbo-Spinal Atrophy, X-Linked/genetics/*physiopathology
;
Disease Progression
;
Female
;
Genes, Recessive
;
Genetic Association Studies
;
Genotype
;
Humans
;
Male
;
Middle Aged
;
Muscle Weakness/*physiopathology
;
Muscular Atrophy, Spinal
;
Muscular Disorders, Atrophic/*genetics
;
Phenotype
;
Receptors, Androgen/*genetics
;
Republic of Korea
;
Trinucleotide Repeats/genetics

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