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Though an increase in Hb AWe reviewed the haematological indices of 47336 individuals to analyse the phenotype-genotype correlation and identified 1439 individuals (3.04%) positive in the elevation of Hb AOf these 1439 individuals with elevated Hb AThis study has provided a mutation spectrum of SUPT5H in a cohort screening leading to the elevation of Hb A

Reactivation of embryonic ζ-globin is a promising strategy for genetic treatment of α-thalassaemia. However, quantification of ζ-globin as a quantitative trait in α-thalassaemia carriers and patients remains incompletely understood. In this study, we aimed to set up a reliable approach for the quantification of ζ-globin in α-thalassaemia carriers, followed by a population study to investigate its expression patterns.ζ-globin was purified as monomers from cord blood haemolysate of a Hb Bart's fetus, followed by absolute protein quantification, which was then tested by in-house ELISA system and introduced as protein standard. It was then used for large-scale quantification in peripheral blood samples from 6179 individuals. Finally, liquid chromatography-tandem mass spectrometry (LC-MS/MS) introduced as an independent validating approach by measuring ζ-globin expression in a second cohort of 141The ELISA system was proved sensitive in distinguishing individuals with varied extent of ζ-globin. Large scale quantitative study of this --Our study has reported reliable approaches for the quantification of ζ-globin and presented the expression patterns of ζ-globin among the

To evaluate the incidence and types of chromosomal abnormalities in pregnancy loss and aborted fetuses with anomaly and compare the performance of subtelomeric MLPA and chromosomal microarray analysis (CMA) in these specimens. Samples were collected from spontaneous miscarriages, stillbirths and aborted fetuses with anomaly between January 2015 and April 2019. Chromosomal abnormalities were detected using subtelomeric MLPA and CMA. Among the 172 miscarriage samples, CMA detected pathogenic chromosomal abnormalities in 88 cases. MLPA could identified all aneuploidies and most pathogenic CNVs, missing all polyploidies; Of the 30 stillbirths, one pathogenic CNV and two VOUS were identified by CMA, all of which were missed from MLPA; Of the 135 aborted fetuses with anomaly, CMA identified pathogenic chromosomal abnormalities in 32 fetuses (23.7%); 18.95% in fetuses with isolated, and 35% in fetuses with multiple anomalies. MLPA can identify all aneuploidies but missing most pathogenic CNVs. Our systematical comparison of subtelomeric MLPA and CMA for chromosomal analysis of tissue from pregnancy loss and aborted fetuses with anomaly is useful for assessing clinical utility of these techniques. MLPA screening, coupled with CMA analysis, is a cost-effective approach to detect chromosomal abnormalities in miscarriage and anomalous fetuses. However, MLPA might not be appropriate for chromosome analysis in stillbirth without structural anomaly; further research with more samples is needed.

Objective To evaluate the utility of clinical exome sequencing (ES)-based carrier screening in Chinese consanguineous couples. Methods Consanguineous couples were screened for autosomal recessive (AR) disorders using the clinical ES of 5000 genes associated with human diseases. Results We recruited 14 couples who elected to have sequencing. One couple was related as first cousins and 13 as second cousins. Both partners carrying the same pathogenic variant were detected in four couples. One couple was found in which one partner carried a splice variant, and the other had a missence variant of the same gene. These five couples were identified as being at risk of having a child affected by an AR disorder. Conclusion Our study demonstrates that ES-based preconception screening yields a clinical value for Chinese consanguineous couples. It enables to detect at-risk couples for rare AR diseases.

Objectives: To present the prenatal findings and the molecular cytogenetic analyses of a de novo interstitial deletion of 1q23.3 encompassing PBX1 gene. Case report: A 32-year-old woman (gravida 1, para 0) underwent amniocentesis at 26 weeks' gestation because of constant small fetal kidneys on prenatal ultrasound. Chromosome microarray analysis (CMA) detected a de novo deletion of 1.871 Mb at 1q23.3. The deletion encompassed 2 genes of PBX1 and LMX1A. PBX1 haploinsufficiency had been reported to lead syndromic congenital anomalies of kidney and urinary tract (CAKUT) in humans. Furthermore, at 31 weeks’ gestation, borderline oligohydramnios and restricted fetal dimensions were revealed. Ultimately, the pregnancy was terminated at 32 weeks with a 1500-g female fetus presenting polydactyl of left hand. Conclusions: The shared phenotypes between this case and the previously published prenatal cases demonstrate that loss of function mutation in PBX1 should be suspicious in fetus with bilateral renal hypoplasia, oligohydramnios and intrauterine growth retardation (IUGR). Keywords: PBX1, Renal hypoplasia, Prenatal diagnosis, Chromosome microarray analysis

The α+-thal deletion of 3.557 kb (NG_000006.1: g.32745_36301del, -αMAL3.5), involving the entire α2-globin gene, was identified in a Chinese family by multiplex ligation-dependent probe amplification (MLPA) followed by gap-polymerase chain reaction (gap-PCR) and sequencing. The proband, a compound heterozygote for this mutant gene and the Southeast Asian (- -SEA; NG_000006.1: g.26264_45564del19301) deletion, had a phenotype of Hb H disease [hemoglobin (Hb) 7.6 g/dL, mean corpuscular volume (MCV) 60.0 fL, Hb H (β4) 0.7%, Hb Bart's (γ4) 2.4% and Hb A2 1.1%]; one of her sisters with same genotype showed a similar phenotype. Another two family members, who were carriers of this mutant gene, had a hematological phenotype of a silent α-thal. The 5' and 3' breakpoints of this deletion are located at the Y2 and Y1 boxes, respectively, therefore, it probably originated from an unequal crossover between these two homologous boxes. This mutation constitutes an additional heterogeneous defect causing α-thal in the Chinese population and would be valuable for elucidating the arrangement in the human α-globin gene cluster.

Background: Abnormal concentrations of maternal thyroid hormones are risk factors for some obstetrical complications. However, the influence induced by different types of maternal thyroid dysfunction on obstetrical complications and outcomes is still controversial.Methods: A total of 17219 pregnant women were drawn for a thyroid function test, including TSH and fT4. All participants were divided into 7 groups, on the basis of their blood tested results, and their pregnancy outcomes were followed up. The isolated hypothyroxinemia group was further divided into 2 cohorts, according to whether they receive levothyroxine. Pregnant complications and outcomes in two cohorts were observed and analyzed.Results: A total of 2621 (15.22%)were identified to have abnormal thyroid function, including 1150 with subclinical hypothyroidism, 526 with gestational transient thyrotoxicosis (GTT), 419 with subclinical hyperthyroidism, 336 with isolated hypothyroxinemia, 78 with hyperthyroidism and 76 with hypothyroidism. Compare to control group, subclinical hypothyroidism, subclinical hyperthyroidism, isolated hypothyroxinemia and hypothyroidism groups presented higher incidence in one or more complications of pregnancy, while, GTT and drug-controlled hyperthyroidism had little significant effect on pregnancy complications. In isolated hypothyroxinemia group, there were no significant difference outcomes between cohorts using levothyroxine and not treatment.Conclusions: Our results showed a high incidence rate of thyroid dysfunction in pregnant women, and subclinical hypothyroidism is most common, followed by GTT. In general, pregnant women with thyroid dysfunction presented high risk of pregnancy complications. Isolated hypothyroxinemia in pregnant women is a matter of concern and treatment with levothyroxine couldn’t improve pregnancy outcomes and obstetrical complications.

Background Xp11.22 duplications have been reported to contribute to nonsyndromic intellectual disability (ID). The HUWE1 gene has been identified in all male Xp11.22 duplication patients and is associated with nonsyndromic ID. Currently, few Xp11.22 duplication cases have been reported in the Chinese population, with limited knowledge regarding the role of other genes in this interval. Case presentation We investigated four unrelated Chinese male Xp11.22 duplication patients, performed a comprehensive clinical evaluation for the patients and discussed the role of other genes in this interval. All patients presented with similar clinical features, including ID, speech impairments and motor delay, which were mostly consistent with those of the Xp11.22 duplication described previously. We searched and compared all cases and noted that one of the probands (Family 1) and DECIPHER case 263,219, who carried small overlapping duplications at Xp11.22 that only covered the entire HSD17B10 gene, also suffered from ID, suggesting the important role of HSD17B10 in this interval. Furthermore, three patients (two probands in Families 3 and 4 and DECIPHER case 249,490) had strikingly similar hypogonadism phenotypes, including micropenis, small testes and cryptorchidism, which have not been previously described in Xp11.22 duplication patients. Interestingly, the FGD1 gene was duplicated only in these three patients. Sufficient evidence has suggested that haploinsufficiency of the FGD1 gene causes Aarskog-Scott syndrome, which is characterized by hypogonadism and other abnormalities. Given that, we are the first group to propose that FGD1 may be a potential dosage-sensitive gene responsible for the hypogonadism observed in our patients. Conclusion We reported novel genotypes and phenotypes in Chinese male Xp11.22 duplication patients, and the HSD17B10 and FGD1 genes may be involved.

In practice, gap-polymerase chain reaction (gap-PCR) and reversed dot-blot are the two most frequently used molecular diagnostic methods for α-thalassemia (α-thal) genotyping. Here, we describe three Chinese individuals from three unrelated families in whom a polymorphism on the α-globin gene cluster led to diagnostic pitfalls. During general molecular diagnosis of thalassemia, three individuals with unexplained results were found. Blood or chorionic villus samples were collected from these three individuals and their family members. Hematological investigations and genetic tests were performed. In Family 1, a polymorphism of HBA2: c.301-24delinsCTCGGCC at the annealing site of the forward primer used in the PCR-reverse dot-blot assay was identified, leading to allele drop-out during the PCR amplification process. In Family 2, a synonymous mutation of C>T substitution at codon 125 of the α2 gene (HBA2: c.376C>T) was identified, leading to the failure of PCR-reversed dot-blot for the HBA2: c.377T>C (Hb Quong Sze or Hb QS) mutation. In Family 3, the size of the PCR fragment from the α2-globin allele carrying the HBA2: c.-771_-428del mutation was smaller and nearly equal to the size of the fragment corresponding to the -α4.2 (leftward) deletion; we also found that the HBA2: c.-771_-428del mutation was linked to a known HBA1: c.-673A>G mutation in this family. In conclusion, diagnostic errors may be caused by technical pitfalls or inherent properties of the DNA sample. All logical steps should be taken to monitor and thus preclude such events.

The α

Objectives The aim of the study was to set up an alternative automatic molecular diagnostic method for deletional α-thalassaemia mutations without gel electrophoresis. Methods Based on the sequence variation within the two Z boxes and melting curve analysis of dually labelled probes, a real-time PCR assay was developed and validated for the rapid detection of major α-genotypes (-- SEA /αα, -- SEA /-α 3.7 , -- SEA /-α 4.2 , -- SEA /-- SEA , -α 3.7 /-α 3.7 and -α 4.2 /-α 4.2 ). Results Samples with the -α 3.7 /-α 3.7 , -α 4.2 /-α 4.2 , -- SEA /αα, -- SEA /-α 3.7 , -- SEA /-α 4.2 , and -- SEA /-- SEA genotypes could be clearly distinguished. The accuracy of this technique for these samples was 100% sensitivity and specificity. Conclusion This technique is rapid and reliable, demonstrating feasibility for use in large-scale population screening and prenatal diagnosis of deletional Hb H disease and Hb Bart's hydrops fetalis.

We identified two novel δ-globin gene mutations in two families during routine thalassemia screening. One missense mutation at codon 73 on the δ-globin gene [δ73(E17)Asp→Val, HBD: c.221A>T] which results in a Hb A2 variant homologous to the β-globin gene variant called Hb Mobile [β73(E17)Asp→Val, HBB: c.221A>T] and we have named this variant Hb A2-Henan. The other is a nonsense mutation [δ7(A4)Glu→Stop, HBD: c.22G>T] which gives rise to a stop codon (TAG) at codon 7, resulting in δ0-thalassemia (δ0-thal). The Hb A2 in one individual with homozygous HBD: c.22G>T was absent.

Background The “gray zone” of borderline hemoglobin A 2 (Hb A 2 ) may be present in a large section of the population, especially in countries where thalassemia is common. However, very little is currently known of the molecular basis of borderline Hb A 2 in Chinese individuals. Method In this study, we performed a comprehensive analysis of the globin genotypes and KLF1 gene mutations associated with borderline Hb A 2 in 165 Chinese subjects. Result Fifteen (9.1%) were positive for a molecular defect in the α-,β-globin genes, of whom, α-thalassemia mutations and α-globin gene triplication were found in eleven cases, accounting for about 73.3% of these globin gene defects. Twenty (12.1%) were positive for a molecular defect in the KLF1 gene. Eight different mutations were identified, six of which are here reported for the first time. The most common is the G176AfsX179 mutation, accounting for 50% of the total. Conclusions The molecular characterization of borderline Hb A 2 in Chinese individuals is significantly different than in Italian population. Our data is conductive to provision of genetic counseling for Chinese individuals with borderline Hb A 2 .

To explore the value of multiplex ligation-dependent probe amplification (MLPA) for the detection of chromosome abnormalities in miscarriage tissues, and to correlate the result with ultrasound findings.A total of 421 cases of spontaneous abortions and fetal deaths were detected with the MLPA method.Among the 421 samples, 232 (55.11%) had an abnormal MLPA result. For the 286 cases derived from13 weeks pregnancy, 206 (72.03%) were abnormal. For the 49 cases from 14-19 weeks pregnancy, 14 (28.57%) were abnormal. For the 86 cases derived after 20 weeks pregnancy, 12 (13.95%) were abnormal. Among the 117 cases with abnormal ultrasound findings, 33 cases (28.21%) had an abnormal MLPA result, 28 out of the 33 cases were numerical chromosome abnormality, 4 cases were chromosome microdeletion and/or micro duplication, 1 case had both numerical abnormality and microduplication. For those with abnormal ultrasound findings for the neck region, fetal edematous syndrome, multiple malformations and digestive system, the detection rates for MLPA were 71.4%, 58.8%, 37.8%, and 9.1%, respectively. For those with abnormal finding of cardiac system, nervous system, face, skeletal system and urinary system, none was found with positive results of MLPA.Numerical chromosomal abnormalities account for the majority of cases with spontaneous abortion. With the increase of gestational age, the occurrence of chromosomal abnormalities gradually declines. Combined ultrasound and MLPA assay can improve the detection rate and accuracy for chromosomal abormalities.

The aim of the present study was to find the most prevalent structural hemoglobin (Hb) variants in southern China and to present hematological and molecular data of abnormal Hbs in the population from southern China. The type and frequency of structural Hb variants and their hematological and molecular characteristics were identified in 131 individuals from 30,848 unrelated partners who were referred to the prenatal clinic of Dongguan MaternalChildren Health Hospital, Dongguan, Guangdong, People's Republic of China (PRC) from 2011 to 2013. α-Globin or β-globin chain variants were screened using a capillary electrophoresis (CE) system, and α-globin or β-globin gene mutations were confirmed using sequencing techniques. The gene frequency of Hb variants was 0.4% (131/30,848). The most common α-globin variants were Hb Constant Spring (Hb CS, HBA2: c.427T C) (0.2%), followed by Hb Q-Thailand (HBA1: c.223G C) and Hb G-Honolulu (HBA2: c.91G C). The most common β-globin variant was Hb E (HBB: c.79G A) (0.09%), followed by Hb New York (HBB: c.341T A). Our results provide a detailed prevalence and molecular characterization of abnormal Hbs in the population of the Dongguan region. These findings have important implications for a region with a high frequency of α- and β-thalassemias.

Hb Constant Spring (Hb CS, HBA2: c.427T > C) is a common nondeletional α-thalassemia (α-thal) that results from a nucleotide substitution at the termination codon of the α2-globin gene. Homozygosity for Hb CS (αCSα/αCSα) is relatively rare, and generally characterized with mild hemolytic anemia, jaundice, and splenomegaly. In this report we present a fetus with cardiomegaly, pericardial effusion, enlarged placenta and increased middle cerebral artery-peak systolic velocity (MCA-PSV) at 24 weeks’ gestation. Fetal blood sampling revealed the severe anemia [hemoglobin (Hb) level being 4.8 g/dL] and Hb H (β4) disease-like hematological findings with Hb Bart’s (γ4) level of 17.9%. DNA sequencing of the α-globin genes found that both partners were Hb CS carriers and the fetus was an Hb CS homozygote. Therefore, this was a rare case of homozygous Hb CS which demonstrated an unusual and serious anemia and hydrops fetalis in utero.

We have identified four Chinese individuals from three unrelated families with raised Hb A2 levels. The anti-Lepore hybrid hemoglobin (Hb) variant was amplified using a pair of primers, 5' to the β-globin gene Cap site and 3' to the δ-globin gene polyadenylation site (polyA) region, respectively. Direct sequencing of the βδ fusion products confirmed the anti-Lepore Hong Kong (NG_000007.3: g.63154_70565dup) variant. We found that this anti-Lepore variant is positioned in zone 3 on the capillary electrophoresis system. It may help in differential diagnosis of Hb variants and providing better information in clinical counseling.

Hb Quong Sze [Hb QS, HBA2: c.377T C (or HBA1)] is a common nondeletional thalassemia in southern China. It is one of the major alleles causing nondeletional Hb H (β4) disease in the Chinese population. There is no strategy currently in place that aims to screen using hematological index cutoffs for this variant. This study was carried out to evaluate whether it is effective to use mean corpuscular hemoglobin (MCH)27.0 pg as a screening test in the first step of screening for Hb QS carriers in southern China. The data of hematological testing in the Hb QS carriers obtained from couples who underwent prenatal thalassemia screening, regardless of the red blood cell (RBC) indices, were retrospectively reviewed. A total of 51 Hb QS carriers were identified, giving a prevalence rate of 0.2%; among these, 45 were Hb QS heterozygotes. The values of hemoglobin (Hb), MCV and mean corpuscular Hb (MCH) in the 45 Hb QS heterozygotes were 13.2 ± 1.8 g/dL, 75.2 ± 3.3 fL and 24.5 ± 0.5 pg, respectively. Eight heterozygotes (17.8%) had an MCV value of80.0 fL, ranging from 80.9 to 84.1 fL, and would not be detected using the cutoff value of MCV80.0 fL as a criterion for thalassemia screening. However, if screening had been based on the MCH27.0 pg value, all 45 Hb QS heterozygotes would have been detected. Using a cutoff value of MCH27.0 pg in nondeletional thalassemia screening would greatly decrease the DNA diagnosis burden.