Table 1.
Similarities and differences - TE and genetic syndromes.
| Characteristics/Phenocopies | Thalidomide Embriopathy | Roberts Syndrome | Duane Radial Ray Syndrome/Okihiro Syndrome | Holt-Oram Syndrome |
|---|---|---|---|---|
| Etiology | Teratogenic | Autosomal Recessive | Autosomal Dominant | Autosomal Dominant |
| Associated gene | Multifactorial | ESCO2 | SALL4 | TBX5 |
| Molecular pathways to which these genes act | Angiogenesis; Oxidative stress; CUL4CRBN complex | Cell Cycle; Establishment of Sister Chromatid Cohesion | Transcriptional regulation of pluripotent stem cells; Heart development and Limb development; Regulation of Wnt-mediated beta catenin signaling and target genes transcription | Heart development; Target genes transcription; Mesenchymal, Embryonic and pluripotent stem cell differentiation and lineage-specific markers; Human embryonic stem cell pluripotency; Limb development |
| Pre-axial limb reduction defect | Absent thumbs, duplicated or with three falanges, radius compromised without affecting the ulna | The thumb is often affected by proximal positioning or digitalization, hypoplasia or agenesis, long bones preferably affected in the following order: radius, ulna and humerus; fibulae, tibiae, and femur | Shortening and radial deviation of forearms, aplasia or hypoplasia of radius, bone hypoplasia of taenial region | Absence, hypoplasia or malformation of tendon bones, carpi and radius |
| Facial | Cleft lips and/or palate (rare), midline hemangioma | Cleft lips and/or palate, microcephaly, hypertelorism | Hypertelorism | Not reported |
| Ocular | Microphthalmia, coloboma | Prominent eyes, corneal opacification | Duane unilateral or bilateral anomaly | They are not characteristic |
| Auditory | Anotia, microtia, deafness | Hypoplastic lobes | Conductive or sensorineural deafness | They are not characteristic |
| Cardiac | Ventricular septal defect, aortic coagulation, tetralogy of Fallot | Ostium secundum atrial septal defect, ventricular septal defect, cardiac conduction defects | Ventricular septal defect, atrial septal defect, tetralogy of Fallot | Atrial septal defect, arrhythmias, ventricular septal defect |
| Genitalia | Cryptorchidism, bicorn or hypoplastic uterus, small or absent penis | Cryptorchidism, large penis relative to the body, increased clitoris | Not reported | Not reported |