Given the crucial role of the personalized management and treatment of hearing loss (HL), etiological investigations are performed early on, and genetic analysis significantly contributes to the determination of most syndromic and nonsyndromic HL cases. Knowing hundreds of syndromic associations with HL, little comprehensive data about HL in genomic disorders due to microdeletion or microduplications of contiguous genes is available. Together with the description of a new patient with a novel 3.7 Mb deletion of the Xq21 critical locus, we propose an unreported literature review about clinical findings in patients and their family members with Xq21 deletion syndrome. We finally propose a comprehensive review of HL in contiguous gene syndromes in order to confirm the role of cytogenomic microarray analysis to investigate the etiology of unexplained HL.

BACKGROUND: With advances in prenatal diagnostic techniques, chromosomal microdeletions and microduplications have become the focus of prenatal diagnosis. 7q partial monosomy or trisomy due to a deletion or duplication of the 7q end is relatively rare and usually originates from parents carrying a balanced translocation.
METHODS: Noninvasive prenatal screening (NIPT) showed a fetus with partial deletion and duplication of chromosome 7q. It was not possible to determine whether the fetus was normal.
METHODS: Conventional chromosome G-banding and chromosome microarray analysis (CMA) were performed on fetal amniotic fluid samples and parental peripheral blood samples.
METHODS: The pregnant women were given detailed genetic counseling by clinicians.
RESULTS: The fetal karyotype was 46, XY on conventional G-banding analysis. The CMA test results showed a deletion of approximately 7.8 Mb in the 7q36.1q36.3 region and a duplication of 6.6Mb in the 7q35q36.1 region. The parents\' karyotype analysis and CMA results were normal, indicating a new mutation.
CONCLUSIONS: CMA molecular diagnostic analysis can effectively detect chromosomal microdeletions or microduplications, clarify the relationship between fetal genotype and clinical phenotype, and provide a reference for prenatal diagnosis of chromosomal microdeletion-duplication syndrome.

Until a few years ago, it was believed that the gradual mosaic loss of the Y chromosome (mLOY) was a normal age-related process. However, it is now known that mLOY is associated with a wide variety of pathologies in men, such as cardiovascular diseases, neurodegenerative disorders, and many types of cancer. Nevertheless, the mechanisms that generate mLOY in men have not been studied so far. This task is of great importance because it will allow focusing on possible methods of prophylaxis or therapy for diseases associated with mLOY. On the other hand, it would allow better understanding of mLOY as a possible marker for inferring the age of male samples in cases of human identification. Due to the above, in this work, a comprehensive review of the literature was conducted, presenting the most relevant information on the possible molecular mechanisms by which mLOY is generated, as well as its implications for men\'s health and its possible use as a marker to infer age.

18p deletion syndrome constitutes one of the most frequent autosomal terminal deletion syndromes, affecting one in 50,000 live births. The syndrome has un-specific clinical features which vary significantly between patients and may overlap with other genetic conditions. Its prenatal description is extremely rare as the fetal phenotype is often not present during pregnancy. Trisomy 8p Syndrome is characterized by heterogenous phenotype, with the most frequent components to be cardiac malformation, developmental and intellectual delay. Its prenatal diagnosis is very rare due to the unspecific sonographic features of the affected fetuses. We present a very rare case of a fetus with multiple anomalies diagnosed during the second trimester whose genomic analysis revealed a 18p Deletion and 8p trisomy Syndrome. This is the first case where this combination of DNA mutations has been described prenatally and the second case in general. The presentation of this case, as well as the detailed review of all described cases, aim to expand the existing knowledge regarding this rare condition facilitating its diagnosis in the future.

Deletions of the long arm of chromosome 20 (20q) are rare, with only 16 reported patients displaying a proximal interstitial 20q deletion. A 1.62 Mb minimal critical region at 20q11.2, encompassing three genes GDF5, EPB41L1, and SAMHD1, is proposed to be responsible for this syndrome. The leading clinical features include growth retardation, intractable feeding difficulties with gastroesophageal reflux, hypotonia and psychomotor developmental delay. Common facial dysmorphisms including triangular face, hypertelorism, and hypoplastic alae nasi were additionally reported. Here, we present the clinical and molecular findings of five new patients with proximal interstitial 20q deletions. We analyzed the phenotype and molecular data of all previously reported patients with 20q11.2q12 microdeletions, along with our five new cases. Copy number variation analysis of patients in our cohort has enabled us to identify the second critical region in the 20q11.2q12 region and redefine the first region that is initially identified. The first critical region spans 359 kb at 20q11.2, containing six MIM genes, including two disease-causing genes, GDF5 and CEP250. The second critical region spans 706 kb at 20q12, encompassing four MIM genes, including two disease-causing genes, MAFB and TOP1. We propose GDF5 to be the primary candidate gene generating the phenotype of patients with 20q11.2 deletions. Moreover, we hypothesize TOP1 as a potential candidate gene for the second critical region at 20q12. Of note, we cannot exclude the possibility of a synergistic role of other genes involved in the deletion, including a contiguous gene deletion syndrome or position effect affecting both critical regions. Further studies focusing on patients with proximal 20q deletions are required to support our hypothesis.

暂无摘要。

BACKGROUND: Williams-Beuren syndrome (WBS) is a rare genetic disorder caused by hemizygous microdeletion of contiguous genes on chromosome 7q11.23. Although the phenotype features extensive heterogeneity in severity and performance, WBS is not considered to be a predisposing factor for cancer development. Currently, hematologic cancers, mainly Burkitt lymphoma, are rarely reported in patients with WBS. Here in, we report a unique case of T-cell acute lymphoblastic leukemia in a male child with WBS.
METHODS: This retrospective study analyzed the clinical data of this case receiving chemotherapy were analyzed. This is a retrospective study.
RESULTS: The patient, who exhibited a typical WBS phenotype and presented with hemorrhagic spots. Chromosomal genome-wide chip analysis (CMA) revealed abnormalities on chromosomes 7 and 9. The fusion gene STIL-TAL1 and mutations in BCL11B, NOTCH1, and USP7 have also been found and all been associated with the occurrence of T-cell leukemia. The patient responded well to the chemotherapy.
CONCLUSIONS: To the best of our knowledge, this is the first reported case of WBS in T-cell acute lymphoblastic leukemia. We want to emphasize that the occurrence of leukemia in this patient might be related to the loss of 7q11.23 and microdeletion of 9p21.3 (including 3 TSGs), but the relationship between WBS and malignancy remains unclear. Further studies are required to clarify the relationship between WBS and malignancy.

DiGeorge syndrome is associated with microdeletion of chromosome 22q11. Hypoplasia of the thymus, hypoparathyroidism, facial malformations and cardiac defects as well as learning difficulties are typical features of the disease. On the other hand hypocalcemia related to hypoparathyroidism is not present in every patient and can develop later and be persistent or transient and is often masked by the other signs or symptoms. We described a 13-year-old boy diagnosed with DiGeorge syndrome, after a few years of nonspecific signs and symptoms, and a microarray examination performed because myopathy was suspected on the basis of elevated creatine kinase activity. Only after molecular confirmation of DiGeorge syndrome the patient was referred to a pediatric endocrinologist and proper therapy started. Looking back to his medical history, low calcium levels were at least 2 times reported in the medical records, the child had learning difficulties, speech disturbances, and submucosal cleft palate suspicion. In conclusion it is important to educate general practitioners and pediatricians to check the serum calcium levels in patients presenting with nonspecific, muscular signs and symptoms.
Zespół DiGeorge\'a jest związany z mikrodelecją w chromosomie 22q11. Typowymi cechami tej choroby są hipoplazja grasicy, niedoczynność przytarczyc, dysmorfia twarzy, występowanie wad serca oraz trudności w nauce. Hipokalcemia związana z niedoczynnością przytarczyc występuje tylko u części pacjentów. Może rozwijać się później niż inne objawy, być trwała lub przemijająca, a często zdarza się, że jest maskowana przez inne dolegliwości. W pracy prezentujemy przypadek 13-letniego chłopca, u którego rozpoznanie zespołu DiGeorge\'a ustalono dopiero po kilku latach występowania niespecyficznych objawów. Badanie mikromacierzy zostało wykonane z powodu podejrzenia miopatii, wysuniętego na podstawie podwyższonej aktywności kinazy kreatynowej w badaniach laboratoryjnych. Dopiero po potwierdzeniu zespołu DiGeorge\'a chłopiec został skierowany do endokrynologa dziecięcego i rozpoczął właściwe leczenie. Analiza historii medycznej pacjenta wskazuje, że w badaniach laboratoryjnych małe stężenia wapnia pojawiały się dwukrotnie, chłopiec miał trudności w nauce, opóźniony rozwój mowy, a także był podejrzewany o podśluzówkowy rozszczep podniebienia. Podsumowując – istotne jest, żeby uczulać lekarzy ogólnych oraz lekarzy pediatrów, aby zlecali badanie stężenia wapnia w surowicy u pacjentów z niespecyficznymi objawami ze strony układu mięśniowego.

OBJECTIVE: We present prenatal diagnosis and perinatal findings of 17q12 microdeletion encompassing HNF1B in a fetus with bilateral hyperechogenic kidneys on fetal ultrasound and mild renal abnormality after birth, and a review of the literature.
METHODS: A 36-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes showed a de novo 1.38-Mb 17q12 microdeletion encompassing LHX1 and HNF1B. The parents did not have such a microdeletion. Prenatal ultrasound showed bilateral hyperechogenic kidneys with normal corticomedullary (CM) differentiation. The parents elected to continue the pregnancy, and a grossly normal 3180-g male baby was delivered at 39 weeks of gestation. aCGH analysis on the cord blood DNA revealed arr [GRCh37 (hg19)] 17q12 (34,856,055-36,248,918) × 1.0 with a 1.393-Mb microdeletion encompassing the genes of MYO19, PIGW, GGNBP2, DHRS11, MRM1, LHX1, AATF, ACACA, TADA2A, DUSP14, SYNRG, DDX52 and HNF1B. When follow-up at age 2 years and 4 months, the renal ultrasound revealed bilateral increased renal echogenicity with normal CM differentiation and small left renal cysts. The blood test revealed BUN = 28 mg/dL (normal: 5-18 mg/dL) and creatinine = 0.5 mg/dL (normal: 0.2-0.4 mg/dL).
CONCLUSIONS: 17q12 microdeletion encompassing LHX1 and HNF1B at prenatal diagnosis may present variable clinical spectrum with bilateral hyperechogenic kidneys on fetal ultrasound and mild renal abnormality after birth. Prenatal diagnosis of fetal hyperechogenic kidneys should raise a suspicion of 17q12 microdeletion syndrome.

BACKGROUND: Autosomal dominant non-syndromic intellectual disability 22 is a rare genetic disorder caused by the ZBTB18 gene. This disorder affects various parts of the body, leading to intellectual disability. It is noteworthy that only 31 cases of this disorder have been reported thus far. As the symptom severity may differ, doctors may face challenges in diagnosing it accurately. It is crucial to be familiar with this disorder\'s symptoms to receive proper diagnosis and essential medical care.
METHODS: There is a case report of a 6-year-old boy who had an unexplained thyroid abnormality, global developmental delay, and an abnormal signal of white matter in brain MRI. However, he did not have growth retardation, microcephaly, corpus callosum hypoplasia, epilepsy, or dysmorphic facial features. Clinical whole exome sequencing revealed a de novo pathogenic variant in the ZBTB18 gene (c.1207delC, p. Arg403Alafs*60), which is a previously unreported site. This variant causes the premature termination of peptide chain synthesis, leading to incomplete polypeptide chains.
METHODS: Autosomal dominant non-syndromic intellectual and disability 22 syndrome and thyroid dysfunction.
METHODS: Rehabilitation training.
RESULTS: The individual is experiencing difficulty with their motor skills, appearing clumsier while running. He struggles with expressing themselves and forming complete sentences, relying mostly on gestures and pointing.
CONCLUSIONS: The clinical presentations of mental retardation, autosomal dominant, type 22 (MRD22) are complicated and varied. Although early diagnosis can be made according to typical clinical symptoms, whole exome sequencing is necessary for diagnosing MRD22, as our study indicates.