Cornelia de Lange syndrome, related disorders, and the Cohesin complex: Abstracts from the 8th biennial scientific and educational symposium 2018.

Cornelia de Lange Syndrome (CdLS), due to mutations in genes of the cohesin protein complex, is described as a disorder of transcriptional regulation. Phenotypes in this expanding field include short stature, microcephaly, intellectual disability, variable facial features and organ involvement, resulting in overlapping presentations, including established syndromes and newly described conditions. Individuals with all forms of CdLS have multifaceted complications, including neurodevelopmental, feeding, craniofacial, and communication. Coping mechanisms and management of challenging behaviors in CdLS, disruption of normal behaviors, and how behavior molds the life of the individual within the family is now better understood. Some psychotropic medications are known to be effective for behavior. Other medications, for example, Indomethacin, are being investigated for effects on gene expression, fetal brain tissue, brain morphology and function in Drosophila, mice, and human fibroblasts containing CdLS-related mutations. Developmental studies have clarified the origin of cardiac defects and role of placenta in CdLS. Chromosome architecture and cohesin complex structure are elucidated, leading to a better understanding of regulatory aspects and controls. As examples, when mutations are present, the formation of loop domains by cohesin, facilitating enhancer-promotor interactions, can be eliminated, and embryologically, the nuclear structure of zygotes is disrupted. Several important genes are now known to interact with cohesin, including Brca2. The following abstracts are from the 8th Cornelia de Lange Syndrome Scientific and Educational Symposium, held in June 2018, Minneapolis, MN, before the CdLS Foundation National Meeting, AMA CME credits provided by GBMC, Baltimore, MD. All studies have been approved by an ethics committee.

Natural history of aging in Cornelia de Lange syndrome.

Observations about the natural history of aging in Cornelia de Lange syndrome (CdLS) are made, based on 49 patients from a multidisciplinary clinic for adolescents and adults. The mean age was 17 years. Although most patients remain small, obesity may develop. Gastroesophageal reflux persists or worsens, and there are early long-term sequelae, including Barrett esophagus in 10%; other gastrointestinal findings include risk for volvulus, rumination, and chronic constipation. Submucous cleft palate was found in 14%, most undetected before our evaluation. Chronic sinusitis was noted in 39%, often with nasal polyps. Blepharitis improves with age; cataracts and detached retina may occur. Decreased bone density is observed, with occasional fractures. One quarter have leg length discrepancy and 39% scoliosis. Most females have delayed or irregular menses but normal gynecologic exams and pap smears. Benign prostatic hypertrophy occurred in one male prior to 40 years. The phenotype is variable, but there is a distinct pattern of facial changes with aging. Premature gray hair is frequent; two patients had cutis verticis gyrata. Behavioral issues and specific psychiatric diagnoses, including self-injury, anxiety, attention-deficit disorder, autistic features, depression, and obsessive-compulsive behavior, often worsen with age. This work presents some evidence for accelerated aging in CdLS. Of 53% with mutation analysis, 55% demonstrate a detectable mutation in NIPBL or SMC1A. Although no specific genotype-phenotype correlations have been firmly established, individuals with missense mutations in NIPBL and SMC1A appear milder than those with other mutations. Based on these observations, recommendations for clinical management of adults with CdLS are made.