Related Experiment Video
Updated: Jul 6, 2026
06:41
In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila
Published on: August 20, 2019
Canine XX DSD (SRY-negative): A Potential Role For The FOXL2 Gene
Summary
Genetic factors beyond SOX9 may cause XX disorders/differences of sex development (DSD) in dogs. FOXL2 is a potential candidate gene, particularly in French Bulldogs, warranting further investigation for improved breeding strategies.
Area of Science:
- Veterinary Genetics
- Reproductive Biology
- Developmental Biology
Background:
- Disorders/differences of sex development (DSDs) are congenital conditions with atypical reproductive system development.
- XX DSD (SRY-negative) involves testicular/ovotesticular tissue in chromosomal females, observed in dogs, cats, and goats.
- Previous canine studies focused on SOX9, identifying limited causative mutations, suggesting other genes are involved.
Purpose of the Study:
- To explore FOXL2 as a candidate gene for 78,XX DSD (SRY-negative) in dogs, particularly French Bulldogs.
- To investigate the genetic underpinnings of XX DSD in a breed predisposed to craniofacial and ocular issues.
- To identify potential genetic factors contributing to XX DSD beyond SOX9.
Main Methods:
- Review of existing literature on canine XX DSD and candidate genes.
- Analysis of functional evidence for FOXL2 in mammalian development.
- Consideration of breed-specific predispositions and genetic relatedness in French Bulldogs.
Main Results:
- FOXL2 is a biologically plausible candidate gene for canine XX DSD.
- Limited SOX9 variations have been found, indicating other genetic factors are likely involved.
- Cryptic relatedness among affected French Bulldogs suggests a shared genetic background.
Conclusions:
- FOXL2 warrants comprehensive sequencing in canine XX DSD cases, especially in French Bulldogs.
- Further research integrating molecular and clinical data is needed to understand XX DSD genetics.
- Identifying causative variants can inform breeding strategies for affected dogs.
Related Concept Videos
01:33Pleiotropy
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,...
02:45The Ratio of X Chromosome to Autosomes
In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined by the ratio of the number of X chromosomes to the number of sets of autosomes. The Y chromosome in Drosophila is active but does not determine sex. It contains genes responsible for the production of sperms in adult flies.
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
01:09Epistasis Analysis
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...
02:50Dosage Compensation
In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one Y chromosome, whereas C.elegans with one X chromosome is a male, and the one with two X chromosomes is a hermaphrodite.
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
01:43Incomplete Dominance
Gregor Mendel's work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid cell has two variants called alleles inherited from each parent. He suggested that amongst these two alleles, one allele is dominant in character and the other recessive. The combination of alleles determines the phenotype of a gene in an organism.
02:32Exon Recombination
The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Exon shuffling follows “splice frame rules.” Each exon has three reading...