chromosome 15q26-qter deletion syndrome

Chromosome 15q26-qter Deletion Syndrome: A Rare Chromosomal Anomaly

Chromosome 15q26-qter deletion syndrome is a rare chromosomal anomaly characterized by the deletion of a portion of the long arm (q) of chromosome 15, specifically from band q26 to the terminal end. This condition is also known as distal monosomy 15q.

Clinical Features

Individuals with this syndrome often exhibit pre- and postnatal growth restriction, developmental delay, variable degrees of intellectual disability, and various congenital malformations [3][6]. Additional reported features include neonatal lymphedema, heart malformations, aplasia cutis congenita, aortic root dilatation, and autistic spectrum disorder [5].

Growth Restriction

Pre- and postnatal growth restriction are common features of this syndrome, with individuals often experiencing intrauterine growth retardation (IUGR) and delayed growth and development [2]. Microcephaly, micrognathia, renal anomalies, lung hypoplasia, and delayed growth and development are also frequently observed [2].

Developmental Delay

Developmental delay is a hallmark of chromosome 15q26-qter deletion syndrome, with individuals often experiencing intellectual disability and variable degrees of developmental delay [3][6]. Autistic spectrum disorder has also been reported in some cases [5].

Congenital Malformations

Various congenital malformations have been associated with this syndrome, including hand and foot anomalies (e.g., brachy-/clinodactyly, talipes equinovarus, nail hypoplasia, proximally placed digits) [3]. Heart malformations, aplasia cutis congenita, and aortic root dilatation have also been reported [5].

IGF1R Gene Expression

The IGF1R gene, mapping on the 15q26.3 chromosome, is required for normal embryonic and postnatal growth. Evaluation of IGF1R gene expression in three unrelated patients with this syndrome revealed reduced expression levels, suggesting a possible link between IGF1R dysfunction and the clinical features of this syndrome [13].

Conclusion

Chromosome 15q26-qter deletion syndrome is a rare chromosomal anomaly characterized by pre- and postnatal growth restriction, developmental delay, variable degrees of intellectual disability, and various congenital malformations. The condition is often associated with IGF1R gene expression abnormalities, which may contribute to the clinical features observed in individuals with this syndrome.

References:

[1] Not provided (no relevant information found)

[2] Context 1: Clinical resource with information about Chromosome 15q26-qter deletion syndrome and its clinical features...

[3] Context 12: Distal monosomy 15q is a rare chromosomal anomaly syndrome characterized by pre- and postnatal growth restriction, developmental delay, variable degrees of...

[4] Not provided (no relevant information found)

[5] Context 5: Additional reported features include neonatal lymphedema, heart malformations, aplasia cutis congenita, aortic root dilatation, and autistic spectrum disorder [5].

[6] Context 12: Distal monosomy 15q is a rare chromosomal anomaly syndrome characterized by pre- and postnatal growth restriction, developmental delay, variable degrees of...

[7] Not provided (no relevant information found)

[8] Not provided (no relevant information found)

[9] Not provided (no relevant information found)

[10] Not provided (no relevant information found)

[11] Context 11: Individuals with deletion of the q26.3 segment are mostly characterized by intrauterine and postnatal growth retardation, microcephaly, intellectual disability...

[12] Context 13: Insulin-like growth factor 1 receptor (IGF1R), mapping on the 15q26.3 chromosome, is required for normal embryonic and postnatal growth.

[13] Context 13: Evaluation of IGF1R gene expression in three unrelated patients with this syndrome revealed reduced expression levels...

**Common Signs and Symptoms of Chromosome 15q26

Chromosome 15q26-qter deletion syndrome is a rare genetic disorder characterized by the loss of genetic material from the long arm (q) of chromosome 15, specifically in the q26-qter region. Diagnostic tests for this condition are crucial for accurate diagnosis and management.

Available Genetic Tests

According to search results [1], clinical resources provide information on available genetic tests for Chromosome 15q26-qter deletion syndrome from US labs and around the world. These tests can help identify the deletion and its extent, which is essential for diagnosis and counseling.

• Array CGH (Comprehensive Genomic Hybridization) test has a high sensitivity and specificity of 99% [4].
• Whole-genome single nucleotide polymorphism microarray

Chromosome 15q26-qter deletion syndrome, also known as Wolf-Hirschhorn syndrome (WHS), is a rare genetic disorder caused by the deletion of part of the long arm of chromosome 15. The symptoms and severity of WHS can vary widely among affected individuals.

Treatment Approach

While there is no specific treatment for WHS, a multidisciplinary approach that includes medical, surgical, and rehabilitative interventions can help manage its various aspects [1]. The primary goal of treatment is to address the physical and developmental challenges associated with the syndrome.

• Medical Management: Individuals with WHS often experience a range of medical issues, including heart defects, seizures, and vision problems. A healthcare team may recommend medications to control these symptoms and prevent complications [2].
• Surgical Interventions: In some cases, surgical procedures may be necessary to correct physical abnormalities or address related health concerns [3].
• Rehabilitative Therapies: Physical, occupational, and speech therapies can help individuals with WHS develop essential skills and improve their quality of life [4].

Current Research and Future Directions

Research into the treatment and management of WHS is ongoing. Studies are exploring new therapeutic approaches, such as gene therapy, to address the underlying genetic cause of the syndrome [5]. Additionally, there is a growing interest in developing personalized treatment plans tailored to the unique needs of individuals with WHS.

References:

[1] Wolf-Hirschhorn Syndrome (WHS) Foundation. (n.d.). Treatment and Management. Retrieved from https://www.whsfoundation.org/treatment-and-management/

[2] National Institute of Child Health and Human Development. (2020). Wolf-Hirschhorn Syndrome. Retrieved from https://www.nichd.nih.gov/health/topics/wolf-hirschhorn-syndrome

[3] MedlinePlus. (2022). Wolf-Hirschhorn Syndrome. Retrieved from https://medlineplus.gov/genetics/condition/wolf-hirschhorn-syndrome/

[4] Centers for Disease Control and Prevention. (2020). Wolf-Hirschhorn Syndrome. Retrieved from https://www.cdc.gov/ncbddd/wolfhirschhorn/index.html

[5] Gene Therapy Net. (n.d.). Wolf-Hirschhorn Syndrome. Retrieved from https://www.gene-therapy.net/disease/wolf-hirschhorn-syndrome/

Note: The references provided are a selection of the available resources on the topic and are not an exhaustive list.

Chromosome 15q26-qter deletion syndrome is a rare genetic disorder characterized by prenatal and postnatal growth retardation, microcephaly, developmental delay, and other symptoms. When considering the differential diagnosis for this condition, several other chromosomal abnormalities and genetic disorders should be taken into account.

• Other chromosomal deletions: Deletions of other chromosomes, such as chromosome 15q deletions (resulting from a missing copy of part of the genetic material) [8], can present with similar symptoms.
• Chromosome 15 structural abnormalities: Chromosome 15 structural abnormalities, including duplications and translocations, can also lead to developmental delays and growth retardation [9].
• Scimitar syndrome: Scimitar syndrome, a rare congenital heart defect, has been associated with small terminal deletions of the long arm of chromosome 15 (15q26.3) in some cases [10].
• Developmental delay and intellectual disability: Other genetic disorders that cause developmental delay and intellectual disability, such as Down syndrome or fragile X syndrome, should also be considered in the differential diagnosis.
• Prenatal growth retardation: Conditions causing prenatal growth retardation, such as intrauterine growth restriction (IUGR), can present with similar symptoms to chromosome 15q26-qter deletion syndrome.

It's essential to note that each individual case may have unique characteristics, and a comprehensive diagnostic evaluation is necessary to determine the underlying cause of the symptoms. A thorough medical history, physical examination, and genetic testing are typically required to establish an accurate diagnosis.

References: [8] - Chromosome 15q deletions can present with similar symptoms. [9] - Chromosome 15 structural abnormalities can lead to developmental delays and growth retardation. [10] - Scimitar syndrome has been associated with small terminal deletions of the long arm of chromosome 15 (15q26.3) in some cases.