Related Experiment Video
Updated: May 9, 2025
05:22
Identification of the Genes Involved in Stomatal Development via Epidermal Phenotype Scoring
Published on: January 20, 2023
1.6K
Evidence that Phenotypic g is Both Formative and Reflective From Four Large Genetically-Informative Samples
Michael A Woodley Of Menie1, Mateo Peñaherrera-Aguirre2, John G R Fuerst3
1Independent Researcher, London, UK.
Summary
General intelligence (g) is both a reflective and formative construct. New research indicates g influences subtest performance and is also shaped by it, suggesting a dual nature.
Area of Science:
- Psychology
- Behavioral Genetics
- Psychometrics
Background:
- The nature of general intelligence (g) is debated: is it a latent cause or an aggregate summary?
- Biometric structural equation models (SEMs) have previously favored a reflective g model.
- Understanding g's construct type is crucial for interpreting genetic and environmental influences.
Purpose of the Study:
- To test whether general intelligence (g) is a reflective or formative construct.
- To compare common pathway, independent pathways, and merged SEMs using genetically informed data.
- To investigate the dual reflective and formative nature of g.
Main Methods:
- Analysis of four large, genetically informed datasets (US and UK).
- Confirmatory Factor Analysis (CFA) to test three competing SEMs: common pathway, independent pathways, and merged.
- Estimation of genetic g using polygenic scores for educational attainment and cognitive abilities.
Main Results:
- The merged model, incorporating both direct and indirect paths, showed the best fit across all datasets.
- Phenotypic g mediated 31% to 81% of genetic g's effects on subtests.
- Evidence supports g functioning as both a reflective and formative construct.
Conclusions:
- General intelligence (g) is best understood as having both reflective and formative properties.
- The merged model provides a more comprehensive framework for understanding g's complex nature.
- Findings advance the psychometric and genetic understanding of general intelligence.
Related Concept Videos
02:27Background and Environment Affect Phenotype
6.4K
Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as temperature, oxygen availability, presence of mutagens, that can alter an organism’s phenotype.
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...
6.4K
01:09Epistasis Analysis
4.8K
Although Mendel chose seven unrelated traits in peas to study gene segregation, most traits involve multiple gene interactions that create a spectrum of phenotypes. When the interaction of various genes or alleles at different locations influences a phenotype, this is called epistasis. Epistasis often involves one gene masking or interfering with the expression of another (antagonistic epistasis). Epistasis often occurs when different genes are part of the same biochemical pathway. The...
4.8K
01:39Epistasis
43.4K
In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence phenotypes in a phenomenon called epistasis. For example, rabbit fur can be black or brown depending on whether the animal is homozygous dominant or heterozygous at a TYRP1 locus. However, if the rabbit is also homozygous recessive at a locus on the tyrosinase gene (TYR), it will have an unshaded coat that appears white, regardless of its TYRP1...
43.4K
01:33Pleiotropy
37.8K
Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...
37.8K
02:32Position-effect Variegation
6.2K
In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread out in the interphase nucleus, others do not. He termed them euchromatin and heterochromatin, respectively. He proposed that the heterochromatin regions reflect a functionally inactive state of the genome. It was later confirmed that heterochromatin is transcriptionally repressed, and euchromatin is transcriptionally active chromatin.
6.2K
00:49Complementation Tests
4.8K
A complementation test is a simple cross to identify whether the two mutations are located on the same gene or different genes. It was first performed by Edward Lewis in the 1940s while working on fruit flies. He developed the test to identify the location and arrangement of different mutations on chromosomes.
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
Organisms heterozygous for different mutations are crossed pairwise in all combinations. If present on different genes, the mutations can complement each other by providing the missing...
4.8K