We previously localized a quantitative trait locus (QTL) on chromosome 6 affecting milk fat and protein concentration to a 4-cM confidence interval, centered on the microsatellite BM143. We characterized the genes and sequence variation in this region and identified common haplotypes spanning five polymorphic sites in the genes IBSP, SPP1, PKD2, and ABCG2 for two sires heterozygous for this QTL. Expression of SPP1 and ABCG2 in the bovine mammary gland increased from parturition through lactation. SPP1 and all the coding exons of ABCG2 and PKD2 were sequenced for these two sires. The single nucleotide change capable of encoding a substitution of tyrosine-581 to serine (Y581S) in the ABCG2 transporter was the only polymorphism corresponding to the segregation status of all 3 heterozygous and 15 homozygous sires for the QTL in the Israeli and U.S. Holstein populations. The allele substitution fixed effects on the genetic evaluations of 335 Israeli sires were –341 kg milk, +0.16% fat, and +0.13% protein (F-value = 200). No other polymorphism gave significant effect for fat and protein concentration in models that also included Y581S. The allele substitution effects on the genetic evaluations of 670 cows, daughters of two heterozygous sires, were –226 kg milk, 0.09% fat, and 0.08% protein (F-value = 394), with partial dominance towards the 581S homozygotes. We therefore propose that Y581S in ABCG2 is the causative site for this QTL.

To examine the relationship between health beliefs and participation in breast cancer screening among Arab women in Israel. A random sample of 568 Arab women, aged 20-60, belonging to three religious groups, Muslim, Christian, and Druze, was recruited. Participants answered a telephone questionnaire regarding attendance for mammography screening and clinical breast examination (CBE) and health beliefs. Christian women had undergone more mammography screening and CBE than Druze and Muslim women. They perceived more benefits and fewer barriers to screening practices and had greater perception of the severity of breast cancer. Perception of susceptibility was similar across groups. The barriers that were significant for the Druze and Muslim women were feelings of discomfort and embarrassment, the belief that there was no cure in the case of a positive finding, perceiving mammography as hazardous to health, and perceiving CBE as painful. Logistic regression revealed that age, group, and having a first-degree relative with breast cancer predicted participation in early detection screening. Physician's recommendation predicted mammography, and level of participants' religiosity predicted CBE. Diversity in health beliefs and behaviors exists in religious subgroups. Health communications should be modified to suit women in different groups in order to increase participation in screening. In addition, physicians have to be made keenly aware of their pivotal role in motivating women to participate in early detection screening.