Related Experiment Video
Updated: Jul 19, 2026
11:20
Osmotic Avoidance in Caenorhabditis elegans: Synaptic Function of Two Genes, Orthologues of Human NRXN1 and NLGN1, as Candidates for Autism
Published on: December 12, 2009
Effect of misoriented sites on neutrality tests with outgroup
Emmanuelle Baudry1, Frantz Depaulis
1Laboratoire d'Ecologie, Centre National de la Recherche Scientifique UMR 7625-EPHE, Université Pierre et Marie Curie, 75252 Paris 05, France.
Genetics
|December 12, 2003
Summary
Homoplasy can lead to incorrect ancestral state inference in population genetics. Our study shows misorientation rates significantly impact Fay and Wu
Area of Science:
- Population genetics
- Evolutionary biology
- Molecular evolution
Background:
- Neutrality tests are crucial for studying molecular evolution.
- Inferring ancestral and derived states relies on outgroup data.
- Homoplasy poses a challenge by causing misidentification of genetic variants.
Purpose of the Study:
- To investigate the impact of homoplasy on neutrality tests.
- To evaluate the influence of misorientation rates on Fay and Wu's H-test.
Main Methods:
- Utilizing polymorphism data and outgroup information.
- Empirically deriving rates of misorientation.
- Analyzing the performance of Fay and Wu's H-test under varying conditions.
Main Results:
- Homoplasy leads to incorrect inference of derived variants.
- Empirically derived misorientation rates significantly affect Fay and Wu's H-test.
- The influence of misorientation is amplified with larger sample sizes.
Conclusions:
- The accuracy of neutrality tests is sensitive to homoplasy.
- Fay and Wu's H-test requires careful consideration of misorientation rates.
- Future studies should account for misorientation to improve ancestral state inference.
Related Concept Videos
01:21Frequency-dependent Selection
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.Positive Frequency-Dependent SelectionIn positive...
01:31In- and Out-Groups
People all belong to a gender, race, age, and social economic group. These groups provide a powerful source of our identity and self-esteem (Tajfel & Turner, 1979) and serve as our in-groups. An in-group is a group that we identify with or see ourselves as belonging to.
02:16Stereotype Content Model
The Stereotype Content Model (SCM) was first proposed by Susan Fiske and her colleagues (Fiske, Cuddy, Glick & Xu, 2002; see also Fiske, 2012 and Fiske, 2017). The SCM specifies that when someone encounters a new group, they will stereotype them based on two metrics: warmth—or that group’s perceived intent, and how likely they are to provide help or inflict harm—and competence—or their ability to carry out that objective. Depending on the warmth-competence categorization, a person will feel...
02:30Chirality at Nitrogen, Phosphorus, and Sulfur
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
01:15Unsymmetric Bending - Angle of Neutral Axis
Unsymmetrical bending occurs when a structural member is subjected to bending moments in a plane that does not align with the member's principal axes. This scenario typically arises in beams and other structural components when loads are applied at non-ideal angles, introducing complexities in stress analysis.
When a bending moment is applied at an angle θ concerning the vertical axis of a symmetrical member, it can be resolved into components along the member's principal centroidal axes. The...
When a bending moment is applied at an angle θ concerning the vertical axis of a symmetrical member, it can be resolved into components along the member's principal centroidal axes. The...
01:23McNemar's Test
McNemar's Test is a nonparametric statistical test used to determine if there is a significant difference in proportions between two related groups when the outcome is binary (e.g., yes/no, success/failure). It is beneficial when we have paired data, such as pre-test/post-test designs, where the same subjects are measured under two different conditions. The test is named after the statistician Quinn McNemar, who introduced it in 1947. It is commonly used in situations where subjects are...