The disclosure relates to methods, compositions, and kits for the early determination of the sex of a fetus. The disclosure also provides methods, compositions, and kits for detecting fetal nucleic acids in biological samples (e.g., cell-free fetal DNA).

The disclosure relates to methods, compositions, and kits for the early determination of the sex of a fetus. The disclosure also provides methods, compositions, and kits for detecting fetal nucleic acids in biological samples (e.g., cell-free fetal DNA).

Disclosed is a sex identification specific DNA sequence and a sex identification method of Chinese mitten crab Eriocheir sinensis. The sex identification specific DNA sequence is showed as SEQ ID NO:1. The sex identification method includes following steps:S1, extracting genomic DNA of Chinese mitten crab Eriocheir sinensis; S2, PCR amplification using the genomic DNA as template; an upstream primer for PCR amplification is as shown in SEQ ID No: 2 and a downstream primer is as shown in SEQ ID No: 3; S3, examining amplified products by agarose electrophoresis, and those with specific amplified bands are females, otherwise they are males. The method has high identification accuracy, is simple and easy to operate, and is suitable for sex identification of Chinese mitten crab Eriocheir sinensis at embryonic and larval stages.

Disclosed is a sex identification specific DNA sequence and a sex identification method of Chinese mitten crab Eriocheir sinensis. The sex identification specific DNA sequence is showed as SEQ ID NO:1. The sex identification method includes following steps:S1, extracting genomic DNA of Chinese mitten crab Eriocheir sinensis; S2, PCR amplification using the genomic DNA as template; an upstream primer for PCR amplification is as shown in SEQ ID No: 2 and a downstream primer is as shown in SEQ ID No: 3; S3, examining amplified products by agarose electrophoresis, and those with specific amplified bands are females, otherwise they are males. The method has high identification accuracy, is simple and easy to operate, and is suitable for sex identification of Chinese mitten crab Eriocheir sinensis at embryonic and larval stages.

The invention relates to a sex determination (SD) marker of a male Mugilidae fish comprising a nucleic acid sequence corresponding to a sequence of a Follicle-stimulating hormone receptor (FSHR) gene of said fish and including at least one male (Y) specific nucleotide difference when compared to a corresponding sequence on a FSHR gene of a female Mugilidae fish. The invention further concerns uses of this sex determination marker in methods of early sex determination in a Mugilidae fish, methods of sex-reversal of a Mugilidae fish prior to appearance of a sex phenotype, and methods for producing a mono-sex population of Mugilidae fishes.

The invention relates to a sex determination (SD) marker of a male Mugilidae fish comprising a nucleic acid sequence corresponding to a sequence of a Follicle-stimulating hormone receptor (FSHR) gene of said fish and including at least one male (Y) specific nucleotide difference when compared to a corresponding sequence on a FSHR gene of a female Mugilidae fish. The invention further concerns uses of this sex determination marker in methods of early sex determination in a Mugilidae fish, methods of sex-reversal of a Mugilidae fish prior to appearance of a sex phenotype, and methods for producing a mono-sex population of Mugilidae fishes.

Various embodiments are directed to applications (e.g., classification of biological samples) of the analysis of the count, the fragmentation patterns, and size of cell-free nucleic acids, e.g., plasma DNA and serum DNA, including nucleic acids from pathogens, such as viruses. Embodiments of one application can determine if a subject has a particular condition. For example, a method of present disclosure can determine if a subject has cancer or a tumor, or other pathology. Embodiments of another application can be used to assess the stage of a condition, or the progression of a condition over time. For example, a method of the present disclosure may be used to determine a stage of cancer in a subject, or the progression of cancer in a subject over time (e.g., using samples obtained from a subject at different times).

Various embodiments are directed to applications (e.g., classification of biological samples) of the analysis of the count, the fragmentation patterns, and size of cell-free nucleic acids, e.g., plasma DNA and serum DNA, including nucleic acids from pathogens, such as viruses. Embodiments of one application can determine if a subject has a particular condition. For example, a method of present disclosure can determine if a subject has cancer or a tumor, or other pathology. Embodiments of another application can be used to assess the stage of a condition, or the progression of a condition over time. For example, a method of the present disclosure may be used to determine a stage of cancer in a subject, or the progression of cancer in a subject over time (e.g., using samples obtained from a subject at different times).

The present invention provides methods for non-invasive determination of sex in a fetus or of Y chromosomal frequency abnormalities—indicative of aneuploidy or sex mosaicisms in a fetus—by detecting and determining the relative contribution genetic sequences from the Y chromosome in view of the percent fetal contribution in a maternal mixed sample.

The present invention provides methods for non-invasive determination of sex in a fetus or of Y chromosomal frequency abnormalities—indicative of aneuploidy or sex mosaicisms in a fetus—by detecting and determining the relative contribution genetic sequences from the Y chromosome in view of the percent fetal contribution in a maternal mixed sample.