Craniosynostotic variations in syndromic, identical twins
Sarah Sher1, Patrick Cole, Yoav Kaufman
1Department of Plastic Surgery, Baylor College of Medicine, Houston, TX 77030, USA.
Annals of Plastic Surgery
|August 30, 2008
Summary
Identical twins with Crouzon syndrome highlight the significant role of environmental factors in craniosynostosis. This case study emphasizes nongenetic influences on syndromic craniosynostosis phenotypes.
Area of Science:
- Genetics
- Developmental Biology
- Environmental Health
Background:
- Syndromic craniosynostosis etiologies are complex and not fully understood.
- Genetic factors are well-studied, but environmental influences remain challenging to characterize.
- Isolating environmental impacts is difficult due to confounding genetic variables.
Observation:
- A case of monozygotic (identical) twin females presenting with Crouzon syndrome is detailed.
- Discordant presentation of craniosynostosis was observed between the twins despite identical genomes.
- This discordance suggests environmental factors contribute to phenotypic variation.
Findings:
- Nongenetic factors significantly impact the phenotype of syndromic craniosynostosis.
- Environmental elements may play a crucial role in the development and severity of craniosynostosis.
- Monozygotic twins provide a unique model for studying environmental influences on genetic conditions.
Implications:
- Understanding environmental contributions can refine diagnostic and therapeutic strategies for craniosynostosis.
- Further research into specific environmental triggers is warranted.
- This case underscores the importance of considering nongenetic factors in syndromic craniosynostosis research.
Related Concept Videos
01:22Sutures of the Skull
The human skull is composed of several bones that come together to protect the brain and support the structures of the face. The junctions where these bones meet are called sutures.
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...
01:14Cranial Bones: Superior and Posterior View
The superior view of the cranium shows the frontal and paired parietal bones.
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
01:08Overview of the Skull
The cranium (skull) is the skeletal structure of the head that supports the face and protects the brain. It is subdivided into the facial bones and the brain case, or cranial vault. The facial bones underlie the facial structures, form the nasal cavity, enclose the eyeballs, and support the teeth of the upper and lower jaws.
The cranial vault surrounds and protects the brain and houses the middle and inner ear structures. This cavity is bounded superiorly by the rounded top of the skull, which...
The cranial vault surrounds and protects the brain and houses the middle and inner ear structures. This cavity is bounded superiorly by the rounded top of the skull, which...
01:27Cranial Bones: Lateral View
The lateral view of the cranium is dominated by temporal, sphenoid, and ethmoid bones.
The temporal bone forms the lower lateral side of the skull. The temporal bone is subdivided into several regions. The flattened upper portion is the squamous portion of the temporal bone. Below this area and projecting anteriorly is the zygomatic process of the temporal bone, which forms the posterior portion of the zygomatic arch. Posteriorly is the mastoid portion of the temporal bone. Projecting...
The temporal bone forms the lower lateral side of the skull. The temporal bone is subdivided into several regions. The flattened upper portion is the squamous portion of the temporal bone. Below this area and projecting anteriorly is the zygomatic process of the temporal bone, which forms the posterior portion of the zygomatic arch. Posteriorly is the mastoid portion of the temporal bone. Projecting...
01:29Nondisjunction
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
01:21Nondisjunction
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold sister...