Genetic heterogeneity in spondyloepiphyseal dysplasia congenita

Area of Science:

• Genetics
• Pediatrics
• Skeletal Dysplasias

Background:

• Spondyloepiphyseal dysplasia congenita (SED congenita) is typically an autosomal dominant skeletal dysplasia.
• Sporadic cases are often attributed to new dominant mutations, with low recurrence risk counseling.

Observation:

• Two unrelated infants presented with short stature and radiographic findings consistent with SED congenita.
• Neither infant had other anomalies, and family histories were unremarkable, with no consanguinity.
• Both families later had a second affected child, contradicting initial genetic counseling.

Findings:

• The occurrence of multiple affected children in these families suggests a different inheritance pattern than initially presumed.
• Clinical and radiographic presentations were indistinguishable from typical autosomal dominant SED congenita within the first three years.
• Autosomal recessive inheritance is the most probable explanation for these cases, indicating genetic heterogeneity.

Implications:

• Genetic counseling for sporadic SED congenita in infants requires consideration of potential autosomal recessive inheritance.
• Diagnostic and genetic evaluation may need to account for conditions that mimic autosomal dominant SED congenita.
• Further research into the genetic basis of SED congenita is warranted to understand its heterogeneity.