OBJECTIVE: To explore the correlation between structural chromosomal abnormality and clinical characteristics of a child featuring gonadal dysplasia.
METHODS: A 13-year-old child who was admitted to Lianyungang Maternal and Child Health Care Hospital on February 7, 2023 for primary amenorrhoea and occasional abdominal pain was selected as the study subject. Clinical data of the child was collected, and peripheral blood samples of the child and her parents were collected. G-banding chromosomal karyotyping and copy number variation sequencing (CNV-seq) were carried out. \"Pseudodual centromere isochromosome X\" and \"psu idic(X)\" were used as keywords to search the CNKI, Wanfang and PubMed databases, and the search period was set as from January 1, 2002 to June 1, 2023. Relevant literature on the structural abnormality of X chromosome was searched and analyzed retrospectively.
RESULTS: The child has a height of 153 cm and weighed 45 kg. She has no obvious facial dysmorphism. Laboratory tests showed that she had higher FSH and luteinizing hormone, and lower E2. Ultrasonography showed that she had small ovaries and rudimentary uterus. She was found to have a karyotype of 46,X,psu idic(X)(q21.3)[40]/mos 45,X[3], whilst both of her parents had a normal karyotype. CNV-seq showed that she had a 63.27 Mb deletion in Xq21.32q28 and a 91.59 Mb duplication in Xp22.33q21.32 (mosaicism rate = 74%). A total of 11 relevant literature were retrieved. Clinical phenotypes of patients with similar structural chromosomal abnormalities were diverse, which was closely related to the mosaicism rate of the 45,X karyotype and the location of the breaking point.
CONCLUSIONS: 46,X,psu idic(X)(q21.3)/45,X probably underlay the dysplasia of uterus and ovary and sex hormone abnormalities in this child, while her height was spared. Deletion of Xq21.32q28 is a key factor leading to Turner syndrome-like phenotype such as rudimentary uterus and ovarian dysplasia.

OBJECTIVE: To explore the genetic characteristics of a fetus with sex chromosome abnormality indicated by non-invasive prenatal testing (NIPT) at 25+ gestational weeks.
METHODS: A pregnant woman who was admitted to the Taizhou Hospital for abnormal NIPT result on January 6, 2023 was selected as the study subject. Relevant clinical data was collected. The fetus was subjected to chromosomal karyotyping analysis, copy number variation sequencing (CNV-seq), fluorescence in situ hybridization (FISH), and multiplex PCR assays.
RESULTS: NIPT had suggested monosomy of X chromosome. The fetus was found to have a chromosomal karyotype of 45,X[59]/46,X,del(Y)(q11.2)[17] at 30+ weeks of gestational age. CNV-seq suggested the presence a 7.98 Mb deletion at Yq11.222q12 and a mosaicism 16.92 Mb deletion. FISH suggested that the fetus harbored two SRY genes and a mosaicism sex chromosomal abnormality, and multiplex PCR revealed that its AZF b+c region was completely deleted. C-banded karyotyping showed darkly stained dense mitotic granules at both ends of the Y chromosome. The fetus was ultimately determined as a 45,X/46,X,idic(Y)(q11.2) mosaicism. Following elected abortion, testing of the fetal tissue confirmed the presence of 45,X/46,XY mosaicism, and CNV-seq result of the placental tissue was compatible with that of NIPT. CNV-seq analysis of the couple revealed no obvious abnormality.
CONCLUSIONS: With combined NIPT, karyotyping, CNV-seq, FISH and multiplex PCR assays, the fetus was diagnosed as a 45,X/46,X,idic(Y)(q11.2) mosaicism with deletion of the AZF b+c region. Above finding has enabled prenatal diagnosis for the fetus.

BACKGROUND: Male infertility has become a global health problem, and genetic factors are one of the essential causes. Y chromosome microdeletion is the leading genetic factor cause of male infertility. The objective of this study is to investigate the correlation between male infertility and Y chromosome microdeletions in Hainan, the sole tropical island province of China.
METHODS: We analyzed the semen of 897 infertile men from Hainan in this study. Semen analysis was measured according to WHO criteria by professionals at the Department of Reproductive Medicine, the First Affiliated Hospital of Hainan Medical University, where samples were collected. Y chromosome AZF microdeletions were confirmed by detecting six STS markers using multiple polymerase chain reactions on peripheral blood DNA. The levels of reproductive hormones, including FSH, LH, PRL, T, and E2, were quantified using the enzyme-linked immunosorbent assay (ELISA).
RESULTS: The incidence of Y chromosome microdeletion in Hainan infertile men was 7.13%. The occurrence rate of Y chromosome microdeletion was 6.69% (34/508) in the oligozoospermia group and 7.71% (30/389) in the azoospermia group. The deletion of various types in the AZF subregion was observed in the group with azoospermia, whereas no AZFb deletion was detected in the oligozoospermia group. Among all patients with microdeletions, the deletion rate of the AZFc region was the higher at 68.75% (44 out of 64), followed by a deletion rate of 6.25% (4 out of 64) for the AZFa region and a deletion rate of 4.69% (3 out of 64) for the AZFb region. The deletion rate of the AZFa region was significantly higher in patients with azoospermia than in patients with oligozoospermia (0.51% vs. 0.39%, p < 0.001). In comparison, the deletion rate of the AZFc region was significantly higher in patients with oligozoospermia (3.08% vs. 6.30%, p < 0.001). Additionally, the AZFb + c subregion association deletion was observed in the highest proportion among all patients (0.89%, 8/897), followed by AZFa + b + c deletion (0.56%, 5/897), and exclusively occurred in patients with azoospermia. Hormone analysis revealed FSH (21.63 ± 2.01 U/L vs. 10.15 ± 0.96 U/L, p = 0.001), LH (8.96 ± 0.90 U/L vs. 4.58 ± 0.42 U/L, p < 0.001) and PRL (263.45 ± 21.84 mIU/L vs. 170.76 ± 17.10 mIU/L, p = 0.002) were significantly increased in azoospermia patients with microdeletions. Still, P and E2 levels were not significantly different between the two groups.
CONCLUSIONS: The incidence of AZF microdeletion can reach 7.13% in infertile men in Hainan province, and the deletion of the AZFc subregion is the highest. Although the Y chromosome microdeletion rate is distinct in different regions or populations, the regions mentioned above of the Y chromosome may serve an indispensable role in regulating spermatogenesis. The analysis of Y chromosome microdeletion plays a crucial role in the clinical assessment and diagnosis of male infertility.

BACKGROUND: Chromosomal abnormalities occur in the equine population at a rate of approximately 2%. The use of molecular cytogenetic techniques allows a more accurate identification of chromosomal abnormalities, especially those with a low rate of abnormal metaphases, demonstrating that the actual incidence in equine populations is higher.
OBJECTIVE: Estimation of the number of carriers of karyotypic abnormalities in a sample from a population of young horses of various breeds, using molecular cytogenetic techniques.
METHODS: Cross-sectional.
METHODS: Venous blood samples were collected from 500 young horses representing 5 breeds (Purebred Arabian, Hucul, Polish primitive horse [Konik], Małopolska, Coldblood, Silesian). Chromosomes and DNA were obtained from blood lymphocytes and evaluated by fluorescence in situ hybridisation (FISH) and PCR, using probes and markers for the sex chromosomes and select autosomes.
RESULTS: Nineteen horses, 18 mares and 1 stallion, were diagnosed with different chromosomal abnormalities: 17 cases of mosaic forms of sex chromosome aneuploidies with a very low incidence (0.6%-4.7%), one case of a SRY-negative 64,XY sex reversal mare, and one mare with X-autosome translocation. The percentage of sex chromosomal aberrations was established as 3.8% in the whole population, 6.08% in females and 0.49% in males.
CONCLUSIONS: Limited sample size, confined to horses from Poland.
CONCLUSIONS: The rate of sex chromosomal abnormalities we identified was almost double that reported in previous population studies that used classical chromosome staining techniques. FISH allowed the detection of aneuploid cell lines which had a very low incidence. The FISH technique is a faster and more precise method for karyotype examination; however, it is usually focused on only one or two chromosomes while banding karyotyping includes the entire chromosome set.

BACKGROUND: To describe and conclude the in vitro fertilization (IVF) results of patients with X chromosome abnormality.
METHODS: A retrospective case series was conducted. According to the number of normal X, patients were allocated into two groups: Group A (patients with only a normal X, while other X has any types of abnormalities) and Group B (patients have two or more normal X chromosomes). Clinical data, including basic information, fertility information, and IVF outcomes, were collected.
RESULTS: Fourteen patients with X chromosome abnormality were included, among which 13 patients underwent a total of 29 cycles. Patients in Group B had five successful pregnancies and three live births, while no patient in Group A had a clinical pregnancy. Furthermore, the blastocyst formation rate and incidence of pregnancy were significantly lower in Group A (Z = -3.135, p = .002; Z = -2.946, p = .003, respectively). When controlled covariates, the karyotype of one normal X was also a risk factor for both blastocyst formation rate and success pregnancy (β = .820, 95% confidence interval [CI] = 0.458-1.116, β = .333, 95% CI = 0.017-0.494, respectively).
CONCLUSIONS: Our results revealed that women with only one normal X might suffer from worse IVF outcomes, mainly blastocyst formation rate, compared with those who had two or more normal X, including mosaic Turner syndrome and 47,XXX.

The phenomenon of sex chromosome loss from hematopoietic cells is an emerging indicator of biological aging. While many methods to detect this loss have been developed, enhancing the field, these existing methods often suffer from being labor-intensive, expensive, and not sufficiently sensitive. To bridge this gap, a novel and more efficient technique is developed, named the SinChro assay. This method employs multiplexed single-cell droplet PCR, designed to detect cells with sex chromosome loss at single-cell resolution. Through the SinChro assay, the age-dependent increase in Y chromosome loss in male blood is successfully mapped. The age-dependent loss of the X chromosome in female blood is also identified, a finding that has been challenging with existing methods. The advent of the SinChro assay marks a significant breakthrough in the study of age-related sex mosaicism. Its utility extends beyond blood analysis, applicable to a variety of tissues, and it holds the potential to deepen the understanding of biological aging and related diseases.

49,XXXYY is an extremely rare sex chromosomal aneuploidy (SCA), with only seven cases reported worldwide to date. Among these cases, only three have been documented into adulthood. Moreover, no cases of 49,XXXYY have been reported in Japan. This SCA has been identified in two scenarios: in vitro fertilization and abortion. Similar to 47,XXY, this aneuploidy is a type of Klinefelter syndrome. Aneuploidy of the X chromosome can lead to various progressive complications due to excess X chromosomes. Herein, we present the case of a Japanese man with 49,XXXYY. He exhibited developmental delays and external genitalia abnormalities since early infancy but was not closely monitored for these symptoms until the age of 3 years old. At that time, a chromosome test revealed his karyotype to be 49,XXXYY. Subsequent examinations were conducted due to various symptoms, including delayed motor development, intellectual disability, facial dysmorphisms, forearm deformities, hip dysplasia, cryptorchidism, micropenis, primary hypogonadism, and essential tremor. Since reaching puberty, he has undergone testosterone replacement therapy for primary hypogonadism, experiencing no complications related to androgen deficiency to date. He has maintained normal lipid and glucose metabolism, as well as bone density, for a prolonged period. There are no other reports on the long-term effects of testosterone treatment for the SCA. Appropriate testosterone replacement therapy is recommended for individuals with 49,XXXYY to prevent complications. This report will contribute to an enhanced understanding of the 49,XXXYY phenotype, aiding in the diagnosis, treatment, and genetic counseling of future cases.

OBJECTIVE: To explore the genetic basis for a patient with Disorders of sex development (DSD).
METHODS: A female patient who had presented at the Linyi People\'s Hospital due to primary amenorrhea on April 6, 2022 was selected as the study subject. Conventional chromosomal karyotyping, fluorescence in situ hybridization (FISH), chromosomal microarray analysis (CMA), fluorescence quantitative PCR and Sanger sequencing were carried out for the patient.
RESULTS: The patient, a 14-year-old female, had featured short statue, multiple nevi, and primary amenorrhea. She was found to have a karyotype of 46,X,idic(Y)(p11.3)[59]/45,X[39]/47,X,idic(Y)(p11.3)×2[2]. The result of FISH assay was 46,X,der(Y).ish idic(Y)(p11.3)(SRY+)[59]/45,X[39]/47,X,der(Y)×2.ish idic(Y)(p11.3)(SRY+)[2]. That of CMA was arr[GRCh37](X)×1,(Y)×0-1,arr[GRCh37]Yp11.32(118552_472090)×1. The patient had no deletion in the AZF region of Y chromosome, and was negative for variant of SRY gene. Combining the above results, her molecular karyotype was determined as mos 46,X,idic(Y)(p11.32)[59]/45,X[39]/47,X,idic(Y)(p11.32)×2[2].ish 46,X,idic(Y)(p11.32)(DXZ1+,DYZ1++,DYZ3++,SRY+)[59]/45,X(DXZ1+,DYZ1-,DYZ3-,SRY-)[39]/47,X,der(Y)×2.ish idic(Y)(p11.32)(DXZ1+,DYZ1++,DYZ3++,SRY+)[2].arr[GRCh37](X)×1, (Y)×0-1，arr[GRCh37]Yp11.32(118552_472090)×1. The patient was diagnosed with mosaicism DSD with idic(Y)(p11.32).
CONCLUSIONS: The abnormal mosaicism karyotype probably underlay the DSD in this patient.

OBJECTIVE: To determine the frequency and characteristics of AZF microdeletions of Y chromosome and karyotypic abnormalities among infertile male patients from southwest China.
METHODS: 4 278 infertile male patients treated at West China Second University Hospital of Sichuan University from September 2018 to July 2023 were selected as the study subjects. Results of Y chromosome microdeletion detection and G-banded karyotyping analysis were retrospectively reviewed.
RESULTS: Clinical data of the patients were collected, which have included 2 048 patients with azoospermia, 1 536 patients with oligozoospermia, 310 patients with mild to moderate oligozoospermia, and 384 patients with infertility but normal sperm concentration. An abnormal karyotype was found in 213 (8.80%) of 2 421 patients who had undergone karyotyping analysis. The frequency of Y chromosome microdeletions was 9.86% (422/4 278), which had occurred in 10.4%, 13.28%, 0.97% and 0.52% of the cases with azoospermia, severe oligozoospermia, mild to moderate oligozoospermia, and infertility with normal sperm concentration, respectively.
CONCLUSIONS: Y chromosome microdeletion detection and karyotyping analysis are crucial for assessing the cause of male infertility. Early diagnosis can facilitate the selection of reproductive methods.

BACKGROUND: The diagnosis of supernumerary X & Y chromosome variations has increased following the implementation of genetic testing in pediatric practice. Empirical evidence suggests that the delivery of the diagnosis has a lasting impact on how affected individuals and their parents perceive and adapt to the diagnosis. The purpose of this review is to synthesize the literature to obtain useful recommendations for delivering a pediatric diagnosis of a sex chromosome multisomy (SCM) based upon a growing body of quantitative and qualitative literature on patient experiences.
METHODS: We conducted an integrative literature review using PubMed, Web of Science and CINAHL employing keywords \"genetic diagnosis delivery,\" \"genetic diagnosis disclosure,\" \"sex chromosome aneuploidy,\" \"Klinefelter syndrome\" or \"\"47, XXY,\" \"Jacob syndrome\" or \"47, XYY,\" \"Trisomy X,\" \"Triple X\" or \"47, XXX,\" and \"48 XXYY from January 1, 2000, to October 31, 2023.
RESULTS: Literature supports that patients and parents value the provision of up-to-date information and connection with supportive resources. Discussion of next steps of care, including relevant referrals, prevents perceptions of provider abandonment and commitment to ongoing support. Proactively addressing special concerns such as disclosing the diagnosis to their child, family, and community is also beneficial. Tables are provided for useful information resources, medical specialties that may be required to support patients, and common misconceptions that interfere with accurate information about the diagnosis.
CONCLUSIONS: Patient experiences suggest there should be heightened attention to diagnosis delivery, in reference to the broader ethical and social impacts of a SCM diagnosis. We present recommendations for optimal disclosure of a SCM diagnosis in early and late childhood, adolescence, and young adulthood.