Biomedical subjects

D G J Jennen

Publications and source records attributed to D G J Jennen.

6 recordsLinked to original sources

PubMed2006

Haplotype analysis of beta-actin gene for its association with sperm quality and boar fertility.

beta-actin (ACTB) was examined as a direct functional candidate gene for the possible association with sperm concentration, motility (MOT), semen volume per ejaculate, plasma droplet rate, abnormal sperm rate (ASR) and the fertility traits, non-return rate and number of piglets born alive (NBA). Three polymorphisms in intron 3 (T>C) and one polymorphism in exon 4 (T>C) of porcine ACTB gene were identified by comparative sequencing of animals of the breeds Pietrain and Hampshire. Association analysis revealed that haplotypes affected the variation of the traits MOT, ASR and NBA. The beneficial haplotypes may provide considerable improvement of sperm quality and fertility in the tested commercial boar population.

Actins↗

PubMed2005

Candidate gene markers for sperm quality and fertility of boar.

Candidate genes gonadotropin releasing hormone receptor (GNRHR), prolactin (PRL), prolactin receptor (PRLR), follicle-stimulating hormone beta (FSHB), luteinizing hormone beta (LHB), follistatin (FST), inhibin alpha (INHA), inhibin beta A (INHBA) and inhibin beta B (INHBB) were investigated for their association with sperm quality traits of sperm concentration (SCON), motility (MOT), semen volume per ejaculate (VOL), plasma droplets rate (PDR), abnormal sperm rate (ASR) and fertility traits of non return rate (NRR) and number of piglets born alive (NBA). The experimental material included 356 boars of Pietrain (PI) and Pietrain x Hampshire (PI x HA). Analysis of variance revealed significant association of GNRHR with MOT (P = 0.0161), PDR (P = 0.0048) and ASR (P = 0.0201), INHBA was found to have significant effects on PDR (P = 0.0318) and ASR (P = 0.0067), INHBB was significant (P = 0.0360) for SCON trait. FSHB, FST, INHA, PRL, PRLR and LHB had no significant effects on any trait in this experiment.

Analysis of Variance↗

PubMed2005

Polymorphisms in candidate genes as markers for sperm quality and boar fertility.

Alpha-actinins (ACTN1 and ACTN4) and gamma-actin (ACTG2), were investigated as candidate genes on the basis of their known functions, for their possible association with sperm concentration, motility, semen volume per ejaculate, plasma droplets rate, abnormal sperm rate and the fertility traits, non-return rate and number of piglets born alive. Polymorphisms were identified in intron 18 (G>A) of the porcine ACTN1 gene and in exon 22 (A>C) of the porcine ACTN4 gene by comparative sequencing of animals from the Pietrain (PI) and Hampshire (HA) breeds. Pietrain (n = 244) and crossbreed PI x HA (n = 112) boars from an artificial insemination boar station were genotyped for the single nucleotide polymorphisms (SNPs) within ACTN1 and ACTN4 as well as for a previously described microsatellite within ACTG2. The study provides evidence for effects of ACTN1 on fertility and of ACTG2 on sperm quality traits, while no indication of impact of ACTN4 on any of these traits was found.

Actinin↗

PubMed2004

Detection and localization of quantitative trait loci affecting fatness in broilers.

A cross between 2 genetically different outcross broiler dam lines, originating from the White Plymouth Rock breed, was used to produce a large 3-generation broiler population. This population was used to detect and localize QTL affecting fatness in chicken. Twenty full-sib birds in generation 1 and 456 full-sib birds in generation 2 were typed for microsatellite markers, and phenotypic observations were collected for 3 groups of generation 3 birds (approximately 1,800 birds per group). Body weight, abdominal fat weight, and percentage abdominal fat was recorded at the age of 7, 9, and 10 wk. To study the presence of QTL, an across-family weighted regression interval mapping approach was used in a full-sib QTL analysis. Genotypes from 410 markers mapped on 25 chromosomes were available. For the 3 traits, 26 QTL were found for 18 regions on 12 chromosomes. Two genomewise significant QTL (P < 0.05) were detected, one for percentage abdominal fat at the age of 10 wk on chicken chromosome 1 at 241 cM (MCW0058 to MCW0101) with a test statistic of 2.75 and the other for BW at the age of 10 wk on chicken chromosome 13 at 9 cM (MCW0322 to MCW0110) with a test statistic of 2.77. Significance levels were obtained using the permutation test. Multiple suggestive QTL were found on chromosomes 1, 2, 4, 13, 15, and 18, whereas chromosomes 3, 7, 10, 11, 14, and 27 had a single suggestive QTL.

Abdomen↗

PubMed2004

A radiation hybrid map of chicken chromosome 15.

We have constructed a radiation hybrid (RH) map of chicken chromosome (GGA) 15. This map can be used as a resource to efficiently map genes to this chromosome. The map has been developed using a 6000 rad chicken-hamster whole-genome radiation hybrid panel (ChickRH6). In total, six microsatellite loci, 18 sequence tagged sites (STSs) from BAC end sequences and 11 genes were typed on the panel. The initial framework map comprised eight markers, and an additional 23 markers were then added to generate the final map. The total map length was 334 centiRay6000 (cR6000). The estimated retention frequency for the data set was 18%. Using an estimated physical length of 21 Mb, the ratio between cR6000 and physical distance over GGA15 was estimated to be 0.063 Mb/cR6000. The present map increases the marker density and the marker resolution on GGA15 and enables fast mapping of new chicken genes homologous to genes from human chromosomes 12 and 22.

Animals↗

PubMed2002

A comparative map of chicken chromosome 24 and human chromosome 11.

To improve the physical and comparative map of chicken chromosome 24 (GGA24; former linkage group E49C20W21) bacterial artificial chromosome (BAC) contigs were constructed around loci previously mapped on this chromosome by linkage analysis. The BAC clones were used for both sample sequencing and BAC end sequencing. Sequence tagged site (STS) markers derived from the BAC end sequences were used for chromosome walking. In total 191 BAC clones were isolated, covering almost 30% of GGA24, and 76 STS were developed (65 STS derived from BAC end sequences and 11 STS derived within genes). The partial sequences of the chicken BAC clones were compared with sequences present in the EMBL/GenBank databases, and revealed matches to 19 genes, expressed sequence tags (ESTs) and genomic clones located on human chromosome 11q22-q24 and mouse chromosome 9. Furthermore, 11 chicken orthologues of human genes located on HSA11q22-q24 were directly mapped within BAC contigs of GGA24. These results provide a better alignment of GGA24 with the corresponding regions in human and mouse and identify several intrachromosomal rearrangements between chicken and mammals.

Animals↗