[20q11.2 microdeletion syndrome: a phenotypic spectrum expansion. Case report]

Area of Science:

• Genetics
• Genomics
• Rare Diseases

Background:

• 20q11.2 microdeletion syndrome is a rare genetic disorder with a prevalence of less than 1:1,000,000.
• Haploinsufficiency of GDF5, SAMHD1, and EPB41L1 genes contributes to the syndrome's phenotypic manifestations.
• Clinical features encompass craniofacial, limb, neurological, and perinatal abnormalities.

Observation:

• A 5-year-old female presented with hypotonia, psychomotor retardation, microcephaly, and facial dysmorphia.
• Skeletal abnormalities included pectus excavatum, thoracolumbar scoliosis, hip subluxation, camptodactyly, and clinodactyly.
• SNP microarray confirmed a 20q11.21-q11.23 chromosomal region deletion.

Findings:

• The presented case aligns with previously reported features of 20q11.2 microdeletion syndrome.
• New features observed include blepharoptosis, pectus excavatum, scoliosis, and hip dysplasia.
• This expands the documented phenotypic spectrum of the syndrome.

Implications:

• Early and accurate diagnosis through genetic testing is crucial.
• Interdisciplinary management is essential for optimizing patient outcomes.
• Further research is needed to fully understand the genotype-phenotype correlations and long-term prognosis.