Figure - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
G-banding metaphase and karyotype (a) and DAPI-stained metaphase (b) with sSMC (red arrow) that appear ring-like.
Source publication
Background
Microduplications 22q11 have been characterized as a genomic duplication syndrome mediated by nonallelic homologous recombination between region-specific low-copy repeats. Here we report on a 19 years old boy with intellectual disability having an unexpected structurally complex ring small supernumerary marker chromosome (sSMC) originate...
Citations
... Our patient was diagnosed with moderate atopic dermatitis by a dermatologist and is currently being treated with dupilumab. A case of eczema in CES was described previously in a patient with a more severe phenotypic presentation and an unusually larger trisomy and a smaller tetrasomy of proximal 22q11 [15]. Eczema described in the case reported by Fekete et al. resulted from severe hypogammaglobulinemia leading to long infection periods caused by Staphylococcus aureus with grave palmar and plantar eczema. ...
... Eczema described in the case reported by Fekete et al. resulted from severe hypogammaglobulinemia leading to long infection periods caused by Staphylococcus aureus with grave palmar and plantar eczema. Unlike this patient presented by Fekete et al., our patient lacks similar abnormal genetic findings and severe phenotypic features like cardiac defects, musculoskeletal abnormalities, severe immunodeficiency, epilepsy, and malformation of the colon [15]. We do not believe that our patient's rash is a result of skin infections, and in contrast, our patient had elevated immunoglobulins. ...
Cat eye syndrome (CES), also known as Schmid-Fraccaro syndrome, is a complex genetic syndrome with a highly variable phenotype that includes ocular coloboma, anal atresia, preauricular skin tags and pits, heart defects, kidney malformations, dysmorphic facial features, and mild to moderate intellectual disability. We describe a case of a 23-year-old male with a past medical history of CES with short stature, mild learning disability, and some dysmorphic facial features who presented with recurrent pruritus and rashes and had mild liver dysfunction. Furthermore, the patient did not have the classic presentation of CES but a clinically milder expression of the phenotypes. Abnormalities in the abdominal ultrasound prompted an ultrasound-guided liver biopsy, which showed bile ductular proliferation with mild portal inflammation composed of lymphocytes and plasma cells, and bridging fibrosis. The patient's labs showed elevated immunoglobulins with the highest increase observed in IgG, along with negative antinuclear antibodies (ANA), negative anti-mitochondrial antibody, and negative hepatitis A/B/C but a weak positive anti-smooth muscle antibody (ASMA). These findings indicated that the patient most likely had autoimmune hepatitis (AIH) or an overlap syndrome with primary sclerosing cholangitis (PSC). The patient was initially treated with steroids and antihistamines for pruritus, which led to some clinical improvement. After dermatological evaluation, the patient was diagnosed with atopic dermatitis and was recently started on a dupilumab 600 mg loading dose and would continue with biweekly dupilumab 300 mg injections. This dermatological finding may require additional examination and can be a unique presentation in patients with CES. This case illustrates that even patients with milder CES expression can experience intense dermatological complications if not effectively managed. CES is a multifactorial disease that requires intervention from multiple specialists. Therefore, primary care physicians must be aware of the potential complications of CES and make adequate referrals to closely monitor patients' symptoms.
... The diagnosis of sSMC may require molecular and cytogenetic studies, including chromosomal analysis by karyotyping, fluorescent in situ hybridization (FISH), and array CGH [3,[4][5][6][7]. Prenatal diagnosis is always a challenge since the fetal ultrasound findings are unspecific, but an sSMC of chromosome 22 detected at amniocentesis should alert CES [7][8][9]. In both cases, CES was never suspected before birth, and amniocentesis was not performed. ...
... The clinical presentation is variable and does not correlate with genetic content [1,3,[6][7][8][9][10][11]. The classic clinical presentation triad is coloboma of iris, ears and anal malformations, found in around 40% of newborns [1]. ...
Cat-eye syndrome is a rare genetic disease that involves the proximal long (q) arm of chromosome 22. The classic clinical triad includes coloboma of the iris, ears, and anal malformations. This syndrome was named “cat eye” due to the vertical coloboma of the iris. However, the spectrum of clinical manifestations is variable, and the iris coloboma may be absent in 40-50% of cases. Association with congenital heart disease is also frequent and its diagnosis should raise suspicion of a genetic condition. We describe two cases of male infants affected by the cat-eye syndrome, of which no one presented the classic clinical triad. One of them had unpredictable complications that led to prolonged neonatal intensive care unit stay. Although having distinct phenotypes, the diagnosis in both cases was made through nonobstructive total anomalous pulmonary venous return, anal imperforation, and craniofacial anomalies. Iris coloboma was an important clue only in one of them. Prenatal diagnosis is a challenge, such that a genetic study is essential for a final diagnosis in the absence of the classic triad.
... Furthermore, epilepsy is reported being one possible comorbidity in CES (3) as well as in other chromosome 22q11 aberrations. Literature reports few CES patients with different kinds of seizures in their history (6)(7)(8) and more cases of epilepsy in chromosome 22q11 anomalies (9)(10)(11)(12)(13)(14)(15)(16)(17)(18). In the present paper, we report on a young adult with tetrasomy of the region 22q11.1q11.21 ...
... This patient presented total anomalous pulmonary © C I C E d i z i o n i I n t e r n a z i o n a l i venous return surgically treated like elsewhere reported (8) associated with some CES dysmorphic features. Furthermore, the patient presents also some classical physical malformations like ocular hypertelorism (6,7,22), long and asymmetric face (8). From a cognitive and behavioural point of view, the patient presents a severe cognitive disability (7) and a significant impairment in adaptive behaviour and autonomy. ...
... These data are in agreement with previous reports 15,48,49 showing the persistence of small rings during cell divisions. In vivo data corroborate the efficiency of transmission of small CRs during cell division (more than 77% of detected CR) and the familial transmission of mosaic ring syndrome 50,51 . Table 2. Clinical characteristics, modalities of treatment and follow-up of treated Hodgkin lymphoma patients. ...
The mechanisms behind the transmission of chromosomal aberrations (CA) remain unclear, despite a large body of work and major technological advances in chromosome identification. We reevaluated the transmission of CA to second- and third-division cells by telomere and centromere (TC) staining followed by M-FISH. We scored CA in lymphocytes of healthy donors after in vitro irradiation and those of cancer patients treated by radiation therapy more than 12 years before. Our data demonstrate, for the first time, that dicentric chromosomes (DCs) decreased by approximately 50% per division. DCs with two centromeres in close proximity were more efficiently transmitted, representing 70% of persistent DCs in ≥M3 cells. Only 1/3 of acentric chromosomes (ACs), ACs with four telomeres, and interstitial ACs, were paired in M2 cells and associated with specific DCs configurations. In lymphocytes of cancer patients, 82% of detected DCs were characterized by these specific configurations. Our findings demonstrate the high stability of DCs with two centromeres in close proximity during cell division. The frequency of telomere deletion increased during cell cycle progression playing an important role in chromosomal instability. These findings could be exploited in the follow-up of exposed populations.
About 250 cases of ring chromosome 22 (RC22) have been reported in the literature. Approximately 90% of RC22 cases have a deletion of the terminal band, 22q13, compatible with the clinical diagnosis of Phelan-McDermid syndrome (PMS), previously called 22q13 deletion syndrome. The phenotype of these RC22 is consistent with PMS, with intellectual impairment, motor delays, neonatal hypotonia, absent or severely delayed speech, and minor dysmorphic features, although there is a greater predisposition to growth delay in RC22 than in simple deletion of 22q13. It is estimated that about 14% of individuals with PMS have a RC22 but this is likely to be an underestimate. Many individuals with deletion of 22q13 are now diagnosed by chromosomal microarray analysis (CMA), which does not detect the RC. A follow-up karyotype is required, and recommended, to detect the ring following the identification of a terminal deletion of chromosome 22 by CMA. It is imperative to determine if a ring is present, as the additional health risk of developing neurofibromatosis type 2 (NF2) and atypical teratoid rhabdoid tumors (ATRT) accompany the presence of a RC22 in individuals with PMS.
Cat-eye syndrome is associated with abnormalities in chromosome 22. Based on the literature on genetic and clinical characteristics of the disease, three clinical cases observed by the authors at different times are analyzed. Mental retardation of different degree was observed in all cases and schizotypal personality disorder in one case. The latter case is described in detail. The patient's stress due to the mockery of peers and teenagers regarding the characteristics of the patient's features plays a considerable role in the exacerbation of mental illness. Early cosmetic surgical intervention (iris's coloboma removal) is necessary to prevent exacerbations of a mental illness and comfortable existence of the patient in the social environment.
Cat eye syndrome is a clinically recognizable congenital malformation syndrome consisting primarily of colobomas, anal anomalies, preauricular anomalies, cardiac and renal defects, and mild to moderate mental retardation. The name “cat eye” was introduced because of iris colobomas resembling the pupils of the cat.
Cat eye syndrome is a clinically recognizable congenital malformation syndrome consisting primarily of colobomas, anal anomalies, preauricular anomalies, cardiac and renal defects, and mild to moderate mental retardation. The name “cat eye” was introduced because of iris colobomas resembling the pupils of the cat.
