Sara Vanegas, Luz Fernanda Sua, Jaime López-Tenorio, Diana Ramírez-Montaño, Harry Pachajoa

Achondrogenesis type IA (ACG1A) is a rare, lethal autosomal recessive chondrodysplasia affecting endochondral bone ossification and differentiation, causing intrauterine growth restriction, narrow thorax, and short limbs. Mutations in TRIP11, which encodes Golgi microtubule-binding protein 210 in the Golgi apparatus, alter protein transport in tissues. A 28-week gestation male fetus was diagnosed with ACG1A by clinical, radiological, histologic, and molecular findings. Whole exome sequencing was performed on fetal DNA and parental blood. Two fetal heterozygous novel variants of TRIP11, c.2304_2307delTCAA (p.Asn768Lysfs*7) and c.2128_2129delAT (p.lle710Cysfs*19), were inherited from the mother and father, respectively. Both variants created a reading frameshift leading to a premature stop codon and loss of protein function. To our knowledge, this is the first Latin American report with clinical, radiographic, and molecular diagnosis of ACG1A. Clinical and molecular diagnosis in utero is essential for genotype-phenotype correlation and is useful for providing better genetic counseling.